I've long wondered about this question. Say that you normally tip 15% for normal good service in a full-service restaurant. How much should you tip in a restaurant where pretty much everyone eats from a buffet? The waiter takes your drink order, gets you the drink, and gets you the check; the waiter or the busboys clean up after you; the waiter or a busboy takes care of small condiments requests (e.g., to get a bottle of low-sodium soy sauce or stuff like that). Should it still be 15%? 10%, because the waiters do much less than full-service waiters do, and end up serving many more tables? 5%?
More to the point, what's the social norm? There's nothing magical about a 15% tip, or an 18% or 20% tip if some people prefer it — the important thing is that it's a social norm, and becomes part of the deal: You go to a normal restaurant, and you're essentially (morally, if not legally, though there's been one odd legal incident that I know of related to this) promising to pay the cost of the meal plus 15%, unless the waiter's poor service gives you good reason to undertip. What are you promising when you go to a buffet?
I'd love to hear people's views, especially on the descriptive what's-the-social-norm question.
UPDATE: If you're concerned about the waiter's income, keep in mind that because the waiter has to spend less time per table, he will probably be serving more tables. A waiter who is tipped 15% per order at a buffet service restaurant will thus end up making more for the same amount of total work (work per table x number of tables) than a waiter who is tipped 15% per order at a full service restaurant. (The busboys still work pretty much as hard per table, though, and I assume that the tip is split with the busboys, so you can't just proportionately reduce the tip by the reduction in the waiter's amount of work.)
On the other hand, I don't know to what extent this is taken into account in the base salary that the waiter is paid by the restaurant; that, I take it, turns on what the restaurant and the waiters expect the tips to be. And I also have no personal experience confirming my supposition that waiters at buffet restaurants serve more tables than at full-service restaurants, though I think my speculation on this is well-founded. So none of this proves that the rate should be below 15%, but it does suggest that the "buffet restaurant waiters need to live just like full-service restaurant waiters, so they should get the same percentage tip" argument is likely mistaken or at least incomplete.
The food is usualy as bad as the service... or is it the other way around!
Buffet resteraunts comes in drink service, and non drink service. Drink Service is a dollar per person, and non drink service is a dollar or two depending on if you have some ones left over in your wallet. The whole purpose of going to a buffet resteraunt is to do it yourself. When you are remodeling your basement lets say you decide to do the walls and the cealings, but have a guy do the wiring. You dont pay him for all the work he didnt do, you pay him for what he did and no more. I have no problems paying the bus boy and the waiter for what they did. I wont pay them for what they didnt do (getting the food order in, transporting it, answering querries for information, checking the order and delivering the food in a timely manner along with filling the drinks and sorting out the tab into eight seperate tickets). Those activities are all in the cost of fifteen percent.
If you are super high class and had a wine steward, desert cart, and personal visit from the saucier, then I would start thinking 20 or 25. If you are trying to impress your date I suggest not even bothering with the math and leaving an ammount way over the standard to show your casual concern with money if it makes her or him happy with the experience. That last tip also works great if you gave your date the girl menus that didnt have prices.
The other end of this is the bad experience. Horrible service starts getting deductions at like 5 to ten percent. To be fair I think it is just as hard to come down from fifteen as it is to go up from fifteen. The lowest you go for a full service place is one penny. Dont every forget to leave a tip of that ammount at least. It show you were thinking of them when you did and you singled them out for the lowest ammount. Buffet resteraunts have bad service? One single penny again. Displeasure must be show, otherwise they just think of you as incosiderate.
A final note. On Gall. I was at a comedy club and god charged nine dollars and fifty four cents for two diet cokes with one refill a piece. They automatically added the fifteen percent tip, and then left the space blank for me to add more. That burned me alot, and the headliner wasnt all that funny. The autotip is something I am strongly against in any situation where you dont have a large part of eight or more. Any place that does it for any reason under any circumstances gets huge penalties for style and cool. You should be good enough you dont have to worry about a small party. Its a class thing.
Finally, again I might add, lets all work together to stop runaway tip inflation. I have had my friends actually think Im some sort of cold hearted monster because I am not giving the waitress 20 or even 25 percent. Tip inflation makes services we all recive worse. they arent entitled to anything at all really, and the more a waiter or waitress feels he or she is, the worse it gets. I know they cant possibly be living their dream, Monty Pythons the meaning of life aside, and I know they had it rough when choosing their career path on the game of life. Some of us chose to take the extra turn, and go the college route. We paid the tuition, and landed on the lawyer space or what not. Im not going to suffer for the rest of my life because of that.
CNN Corporate Ettiquette suggests a 10% tip at buffets.
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Tipping has become such an ordinary part of life that most travel guides now tell you how to tip when overseas. In a nation where the price of a beer varries from coast to coast, the person bringing you the beer always gets at least fifteen percent. Did waiters create some type of mass marketing campaign that created this mimimum standard?
I certainly hope I never have you as a customer.
Re buffets, Eugene, I tip everywhere the same, including deliveries and even takeout. It's silly, I suppose, but it seems to me that if a server is paid on the assumption that s/he will have such-and-such income in tips, I'm docking his or her pay if I prefer to take my order home and eat it in my own living room, rather than in the restaurant, if I don't pay a tip. I know that a tip is supposed to be rendered for good service, but in practice it's a fraction of wages, and almost always paid routinely. So I do.
I've never denied or reduced a tip based on the service, but I've hardly ever had service bad enough to warrant that.
I believe a dollar per person for a buffet is fine. I agree with the previous comment that at a buffet this is usually not a bad percentage.
Oh yes, and a lower tip for face shrapnel.
My rule of thumb: if I'm not drinking alcohol (no bartender involved, aside from sodas which don't count) and they don't bring me food, what does the tip go toward? The price of food should include basic overhead like cleaning the facilities they provide. Tips are, forgive the old canard, "to incourage prompt service." Or incentivize. Whatever. 20% is outrageous. 10% is outrageous. A buck or so tip for server or bartender if you're ordering something complicated, or something heavy (lots of bottles, say).
Chinese buffets: they add a gratuity when it's 8 or more, I think.
"To-go" where you can sit at their tables: nothing, unless I make a big mess or am otherwise difficult. They gave me food, I paid for it, so what if I'm sitting there? I'm my own wait staff, _I_ deserve the tip.
Self-serve buffet "restaurants" with nice amenities, prompt and polite service, etc.? 10% might be too low. It all varies. Depends on who's ordering off the menu.
Hope that helps.
Eh N.
Don't forget, however, Buffet prices are usually among the lowest for server based dining (as opposed to fast food, order here/pay there/pick up over there...). So working more tables is really necessary to make more money, as there will not be many $100 tables to wait, unless it is a really big group...
It seems like this could be established economically -- if servers at buffet restaurants were making out like bandits, we would expect the best servers to gravitate toward buffet restaurants, openings for servers at these restaurants to be filled quickly, and thus outstanding service at these restaurants. That doesn't jibe with my experience...
Here in California, I generally double the 7.5% sales tax to get the base tip, then add to that based on the quality of service I get. If the service (or food) were so bad as to not justify the 15% base, I ask to speak to the manager.
Nick
I tip a buck per person at buffets, whether it's the Chinese place at 8th and Market or the Bellagio.
But, um:
(morally, if not legally, though there's been one odd legal incident that I know of related to this)
Are you going to leave us hanging? What was that about?
Also, waiters have to "tip put" which means the tip you give your waiter goes towards the bartender and possibly 2 or 3 other people.
If you're willing to pay a whopping $7.50 (15% on a $50 meal for two) for service that includes at least 8 visits to the table so you never have to leave it till you leave the restaurant an hour later, what do you expect to get when you're only paying $1.80 (15% on a cheap $12 meal for two)?
If you're going to pay less, why should you expect equal service?
"Put your 15 or 20 percent tip on the bill, regardless of the type of restaurant or service, and let the restaurant worry about distributing it.
Each of the people you mention is on full working duty during your meal, and worrying about how hard they actually work will only upset your digestion."
(The Washington Post, March 24, 1985)
Since I tend to vastly overtip for inexpensive meals anyway (where an extra dollar can convert an 18% tip to a 30% or 40% one), I've never developed a consistent practice.
If I get seated after someone who arrived later (and without reservations), I'll complain to the manager. I'm not going to take it out on the server.
If the server leaves me sitting there for 20 minutes before greeting me while attending to other customers multiple times, I'll complain to the manager and not tip. Complaining to the manager first offers me a chance to see if another server left sick or something.
If my order isn't right, I'll take my chance that it was the kitchen and still tip the server. Given the limited English proficiency of many cooks, bad stuff happens.
If my server tells me something, like it'll take 20 minutes to get a certain appetizer because they ran out, but I then see another server providing that appetizer to someone else well after "they ran out" and well before I get mine, I'll reduce the tip.
Rude, extremely inattentive, and nonhumorously stoned waitstaff receive reduced or no tips depending on how bad they were.
From that perspective, I leave a dollar or two at buffets. I don't tip at Sonic because they receive at least minimum wage. I don't tip pizza delivery drivers much because they usually earn more than twice minimum wage.
I don't subscribe to tipping better to make up for the low wages paid by the establishment. This is something college students and others need to learn before they go out into the cruel cruel world. Contrary to what you may have learned at the knee of your leftie professors, you have no right to any of my money.
Buffets -- about a buck a person because we rarely ask for more than a glass of water when we sit down. Personal opinion: I hate buffets and would pay a lot to never enter one again. One hitch, my husband loves them above all other food emporia.
More interesting to me is the question of bartenders. Bartenders make much more than waitstaff, yet expect the same tip treatment. However, if it's a madhouse type of bar, where you just squeeze in your order, get your drink, and go, I don't feel any special obligation to tip bartenders extra. Some expect $1 a drink, which often results in a 25% or more tip. However, I just don't consider their work to be as thankless as that of what pure waitstaff does, especially since the bartenders make more, so I tend to tip closer to 10% than 20%. Again, if it's the regular drinking hole, and I have a special relationship to the bartender, I could see tipping more, just because I like the person... but I'm not tipping someone 25% for pouring me a beer, sorry.
In college, I worked as a server at a Pizza hut and it was amazing how many people would order me around for drinks and such, and then not tip me, or at the very most, leave me some loose change. Tipping etiquette seems to be of more concern the more educated and/or wealthy one becomes.
I normally tip 20% which is easy to figure if you look at the pre tax bill and take ten percent of it then double.
A couple of other tipping concerns while you are at it. I often get room service and I wonder what to tip for that. WHat I usually do is look at the room service tip inclusion percentage, usually aroun 15%, and then I add in another five percent or so to take it to 20.
As for the pizza delivery person, I usually tip about 10%. It the bill comes to 20-25 bucks, I usually give three dollars.
I leave a buck at a buffet, two if it's a particularly large bill or I kept the server especially busy. At any buffet at which I'm likely to eat, this usually works out to be somewhere between 10% and slightly more than 25%. I figure it's not worth my time to worry about leaving an exact percentage; I'm not going to sit around waiting for someone to break my $1 bill so that I can leave precisely the right number of pennies.
At normal restaurants, unless the service was bad I calculate 15% and round up to some convenient amount (not more than 20%). I do this partly for convenience, but mostly because I know that some customers are very stingy and some don't tip at all; e.g., some are from cultures in which tipping isn't practiced. Others are just nasty.) I like to help make up the difference. (And before anyone tells me that this isn't my problem: I know it's not. I simply like to be nice to people when I can.)
If the service was bad but I suspect it wasn't the server's fault, I'll likely leave the same tip.
The more expensive the restaurant, the less likely I am to worry about other customers stiffing their servers and, thus, the less likely I am to deliberately overtip. I also assume that more expensive places are better managed, so bad service is more likely to be the fault of the server himself.
Unless there is fondling, in which case: 30%, easy.
They should cut waiters out of the buffet equation altogether. I slaved one summer as a waiter trying to impress at an all-u-r-eating steakhouse. It was not worth it.
But at these buffet restaurants, the waitstaff is generally paid the regular wage, lacking anticipation of tipping. And they didn't used to be taxed on anticipation of tips. So, I rarely tip more than a couple of dollars.
As someone who's been a waiter and a bartender, bartenders don't usually make more in salary. They do make more in tips, on average.
Personally, I tip $1 a drink, just because leaving change seems cheap. Hell, I'm already paying $4 or $5 for what I know is 50 cents worth of liquor, so if it bothered me that much, I'd just drink at home.
If you tip $1 a drink consistently, the bartender isn't going to hold it against you if you only leave 50 cents on your third or fourth drink. At least, I wouldn't.
I *try* to tip at least 15%...When I have the cash (no CC yet; Been leery about such things when in college and without an income source), at least.
Pizza guys: My most common method of food acquisition at school, especially during finals. Have never figured out what to tip, or even if. (It seems a little impolite to ask.) Also, I'm someone who tends to stay very light in terms of actual cash (disability leaves me leery, frankly, of being mugged), and may well have expended my last physical dollar on the food.
So, a question: What *should* I tip pizza delivery guys, especially working for Domino's or such? (Do they pay for gas? Use their own car?)
I've only ever left a penny once, at a pizza hut where we could see our pizzas getting cold on the counter for a good 15 minutes before the waitress showed up and brought them to us. I've also been in a few disasters where the kitchen screwed up, our meal took forever, and the waitress was in the kitchen raising hell, and then got the manager to give us the meal free. Then I left a hefty tip of about 30% of what the bill would have been.
Most of the time when we go out I'm so happy to have somebody else cook and clean up and be nice to my bouncy children that it puts me in a generous mood.
cathy :-)
Fast Food: Nothing - I'm doing all the work.
Bar: $1/round of drinks (one or two drinks)
Restaurant: Sliding scale of 20% or more at cheaper places down to 10% at really expensive places with high-priced drinks. $1/person minimum.
Here's another thing to consider. What if the delivery guy is a grown man that you expect might be trying to support a family instead of the stereotype teenage goof ball? In NYC I rarely get teenager delivery boys. I get delivery MEN. I feel the need to tip them more. Maybe I am a bleeding heart conservative?
So if you're wondering what the average person tips at something like this, it is somewhere around $2 a table, no matter what they actually say they tip (everybody always acts outraged when you tell them of bussing a table with 1 adult and 11 five year olds and getting $2, and yet, it keeps happening).
Finally, a question I can answer! :)
During my pizza delivery days, most of the tips (when they tipped at all) were in the $2-$4 range. If it was a large delivery - like a dozen pizzas for a party or something - the tip would be bigger. When I have a pizza delivered, I try to tip $3 plus whatever change would round the total up to the nearest dollar.
At one place I worked, they provided the cars and paid for the gas. At the other place, I drove my own car and paid for my own gas, but they paid me $1 per delivery to help cover those costs. I don't see too many places any more that provide the vehicles for the drivers, so I'd guess that most of the drivers these days are paying for their own gas.
(No, I've never delivered pizza in my life -- although I did wait tables part time in the Catskills back in the summer of 1968.)
BTW - here in southern NY, I personally tip 20% (incl. tax) because if you patronize the smae places regularly, they really do treat you better.
When younger I spent a lot of time working for Domino's Pizza (never just "Domino's", because of a lawsuit by Domino's Sugar, IIRC).
At the time, drivers made a bit over minimum wage, plus a mileage/maintenance fee, plus tips. The average driver delivered about three pizzas per hour or a bit more during dinner rush. Drivers also answered the phone, cleaned the store, and occasionally helped to make the pizza.
Tips ran about $1 per pizza on average; customers who regularly tipped $2 or more were remembered.
Now I generally tip $2 + the change to round it up to an even dollar amount, even though I live fairly close to my local store*.
* Note that the distance is a major issue, especially in smaller towns. Some customers were a 10-minute one-way drive from the store, which really cuts down on the number of pizzas you can deliver.
When it comes to buffets, I agree with about a buck a person, which is probably about 10% anyway. Less than 15% or 20%, but I did half the work, so they get half the money.
[sorry, couldn't resist]
SMG
Any full-service restaurant: 20%.
Any buffet: 10%
Increase for really, really good service.
Deduct for bad service, down to 0% for truly bad service. With exceptions; I once tipped a waiter 25% on a truly awful job on his first day, since I knew he'd be looking for new job within a week.
"Face Shrapnel" -- I love it! Yes, I'd be more likely to reduce the tip if my wait staff forced me to look at a face full of piercings while I was trying to eat.
At buffet restaurants, I tip something like 10%
Plainly Eugene is an anti-waiter bigot.
Why don't we discuss the tipping habits of different types of groups, not just the overly educated with too much time on their hands.
Iago,
I agree about the absurdity of having codified a sub-minimum wage job into law. I disagree that customers don't appreciate how little waiters are paid. I suspect that the fact that waiters are historically paid little is what led to the practice of tipping in the first place. I also disagree that the attitude you describe is common. I think that attitude would be a better way to do business, but recognizing that is not the way of the world, I follow the social norms when I regularly eat out. Yes, I tip heavier places where I frequent; yes it shows in the service and even the food sometimes.
What bothers me is percentage inflation. 15% became 18%. Why? Because waiter's haven't had a raise in a few years? The price of food goes up, so does their 'salary', even at 15%. I firmly 18% is strategic because most can't be bothered with the 2% math so they tip 20%. Also the big number on the bottom of the bill is post-tax, so most people tip on that. Those 'helpful' percentages on the bottom of a credit card receipt are also post-tax. I read this week an upscale restaurant in DC now adds a mandatory 20% service charge to the bill. I don't recall if that was post-tax.
I agree with a previous poster about the cruel world - if you want to 'rely on the kindness of strangers' so to speak, you have to accept that not everybody is quite so kind (you're going to get stiffed once in a while). Otherwise, they can do what every other entreprenur must do, and put their own price on the service and justify it to the customer. (I can just imagine a waiter carrying around a three-tiered tip price list.)
Lastly, I have yet to hear a cogent argument why waiter's service is worth more when they deliver a steak to the table as opposed to a hamburger.
What Moose said, I understand why tips are more at an upscale restaurant, but prices already reflect that (I do understand why a hamburger costs $1 at McDonald's and $7 at a restaurant). So if there is any tip to be left, I'll leave a dollar or so, even if it's a lot more than 15%.
Didn't the old norm (like in our parents' time) used to be 10% to 12%?
I also object to automatic tips, and have insisted it be removed if it's not on the menu.
ipdbw writes
Deduct for bad service, down to 0% for truly bad service.
It can go lower than 0%. I have had service so bad that not only didn't I tip, but I promised to come back just so that I could stiff them again. Luckily the place closed down before we got the chance, but it made us feel better.
Let's face it- being a waiter requires all the skill of a 10 year old. You basically have to be smart enough to write down what people say, walk to the counter/kitchen, relay that information and then walk back to the table with the food. Yes the pay is horrible- but that's because the position is so absurdly easy and replaceable.
I do know that some people expect that the waiter "entertain" them in some way- that's perfectly fine and I can see where you would give someone money for providing you special services of entertainment. However why should I, who would rather the waiter just go and get my food and then not bug me, be forced into this "societal norm" in which I want no part? I go out for the food- if I should tip anyone, it should be the chef, not the person that manages the incredible feat of walking the food to my table without spilling it. Give credit where credit is due- the servers have no part in the decor, ambiance, food, or anything else.
Emotional arguments aside, can somebody please offer me a sound economic rationale for paying more than the listed price of the good or service?
Does anyone here tip the checkout person at the Megolomart?
Emotional arguments aside, can somebody please offer me a sound economic rationale for paying more than the listed price of the good or service?
The listed price is understood to not include the price of service. If the practice of tipping is no longer practiced, restaurants would have to actually pay their servers so that people would still choose that job, and would therefore have to increase prices to pay the increased wages. That is, the market prices the food assuming that the servers are to be tipped approximately 15%.
Also, if you think waiting tables requires only the skill of a 10-year-old, then you should go wait tables at a restaurant where the servers make 6 figures a year.
I'd like to see a restaurant factor gratuities into their prices and print "our employees do not accept tips" on their menus and see what happens.
Up in Massachusetts, Hannaford's groceries used to deliver. They did not accept tips, and I remember that their service (not just delivery, but also selecting decent produce and the like) was excellent. However, they stopped the delivery business after a couple years. Stop and Shop also delivers in MA, but their delivery staff expect tips.
Granted, this isn't a very favorable argument for waiters — instead of tipping them not much money, let's just make them unemployed! — but why aren't there more places with good food that let you serve yourself and don't add a 20% tax to it?
WHY? Because being a waiter is respectable enough in contrast to cleaning toilets that people will do it, move up, and then act all snotty. Middle class kids can do it, and then complain they did not make enough. Try going around bragging about cleaning toilets. They won't do it.
I have noticed that my female friends who worked as waitresses feel the need to say "we need to tip enough, I was once a waitress and I know what it is like" but "enough" turns out to be MORE THAN ENOUGH at a low end restaurant with undistinguishable service.
Yes, I do tip (I think Iago's story shows someone acting terribly), but overtipping begins to make periodic eating out prohibitively expensive even when you get your girlfriends to go to an inexpensive place that is not supposed to have service. Now I have to tip at the buffet? (That is one place I did not tip.) Of course, maybe eating out should be reserved for the rich. No more donut shops and diners.
Oh, this add twenty percent to the bill stuff is crap, and I always find it in the expensive places. I went to an out of town wedding, ended up in this expensive hotel with a discount. The room service charges a $2.50 fee AND 18% gratuity.
----------------------------------------------------
Chris Lansdown,
I agree. Make them unemployed. I hate going into restaurants that are supposed to be self-serve and have a waitstaff they are trying to pawn off on you to pay as it seems buffet owners are doing in jmcmaster behind the scene buffet story. The owner's atitude is "You can work here. Do not do waitstuff. Do other stuff. Now go beg as if you waited on them."
I don't believe in it.
Society says tip these guys over here, but not those guys over there. They're both serving you food. I call bullsh*t...or, rather, Steve Buscemi does.
Houston Lawyer's comments that waiting tables is low-skill entry level work is just way off-base. It's HARD work. And, the menu knowledge and presentation skills necessary far outstrip, say, a file clerk whose primary job skill was learned in kindergarten. (i.e. the abc's.)
Buffet servers often end up setting up the buffet lines and/or sharing their tips with those who do.
While on the subject, I'll throw out my "I wish" rule: tip for soda refills as if they weren't free. (i.e. tip on the bill amount, plus additional for each refill.)
I earned an average of 25%, which after tipping out to the support staff, left me with 15-18% to take home. I personally tip no less than 15% for passable service, and as high as 30% for great service. I have tipped in excess of 200% for truly remarkable service, but only about three times in my life.
At buffets, I tip anywhere from 10-20%. It would take a heimlich or CPR to get me above 20% at a buffet.
(And in my experience, there aren't any "waiters" anyway. They're all "bus boys".)
Stickdude: I wonder if they place those jars there to encourage tips, or because customers that have chosen to tip in the past created an uncomfortable situation. (no place to put the tip except your pocket, etc.) Just a thought towards causality here.
Let's do a back-of-the envelope. Say 12 tables of 4, average of $30 each. At 15% average per customer, $216 in tips. Now let's assume 36 tables of 4 patrons eating buffet at $9.99 each instead, and a 10% average tip. That's about $144 in tips.
All the drivers knew who the non-tippers were and who the good tippers were -- I kept a notebook in my car -- and if you were delivering pizzas to multiple addresses, the good tippers got theirs first, and the non-tippers got theirs last.
Notorious non-tippers also got less toppings on their pizza, and their 2-liter sodas arrived well-shaken.
Tip your delivery drivers. Remember, they know where you live. I recommend $1 + $1 per pizza. An additional dollar or two will put you in the "good tipper" category.
As for what delivery drivers make: minimum wage + a fixed commission per delivery + tips. The commission was $.50 when I was driving, although I think it's $.75 now. The commission pretty much covers your fuel costs, and does not cover capital depreciation of the vehicle.
All the drivers knew who the non-tippers were and who the good tippers were -- I kept a notebook in my car -- and if you were delivering pizzas to multiple addresses, the good tippers got theirs first, and the non-tippers got theirs last.
Notorious non-tippers also got less toppings on their pizza, and their 2-liter sodas arrived well-shaken.
Some people might call this sort of behavior unprofessional.
There are places that do this. They're called "clubs". My New York club doesn't allow us to tip club staff. London clubs I've visited have the same rule. My simple-minded theory was that the club staff (and the maintenance of the clubhouse) was paid for by our dues and club services (bedrooms, meeting rooms, catering, lunch, dinner, drinks, etc.) were charged to members more or less at cost. In practice club finance is more complicated than this, but the effect is that club staff don't depend on tips for their income and club members don't have to figure out how much to tip 'em.
For what it's worth, on Eugene's original question, there are buffets and buffets. My local Indian restaurant does a buffet lunch which differs little from a non-buffet lunch and when the check arrives at the end of the meal, I add 15%. On the other hand, near where I used to work there was a pizza buffet place which charged you at entry. Once in, you got your own food and drink. No tip.
Let's do a back-of-the envelope. Say 12 tables of 4, average of $30 each. At 15% average per customer, $216 in tips. Now let's assume 36 tables of 4 patrons eating buffet at $9.99 each instead, and a 10% average tip. That's about $144 in tips.
That's pretty good, since you're allowing a 3-to-1 ratio of cost for served food versus buffet. The buffets I go to (primarily Chinese, sometimes Indian, and the occasional American brunch) aren't such great bargains.
Chesler's Rule states that every restaurant is all-you-can-eat, but at some of them you have to order and pay more for that privilege.
In my experience, the quantity of food at a buffet would cost maybe 50% more than the comparable meal a la carte, and sometimes a lot less. If it's a fancy jazz brunch, that's $20 versus $7 for a Grand Slam at Denny's; if the competing option is a restaurant with a good rice plate, the same $7 might get you the same quantity of food, with the major differences being the buffet has more variety and you can start eating faster. (And like the boy who realized that rather than saving a nickel a trip by running behind the streetcar, he could save a dollar a trip by running behind a taxi, you can get get all sorts of relatively costly appetizers and maybe even dessert at the buffet that you wouldn't order if you were at the rice plate place.)
If in the opening calculation the average tab at the non-buffet restaurant were $20, 15% times 12 tables of 4 yeilds the same $144 in tips as at the buffet comparison.
I worked for seven years as a waiter, first in a buffet steakhouse, then in a high-end restaurant, and finally in a chain restaurant. While the buffet job was the least taxing mentally, it was the hardest work I've ever done except for the one summer I roofed houses. High-end serving requires a great deal of knowledge and finesse, but is physically easy. Chain restaurant serving is in-between the two, usually one has a very large menu to learn, but customers aren't going to ask you to describe the subtle differences between varieties of wine.
Incidentally, my favorite server in a movie is the woman in Sideways. She really captures the intelligence and strength that it takes to be a server, even in a restaurant with a big windmill out front.
In terms of tipping at buffets, I always tip a minimum of one dollar per person at the table, because I don't want to be one of those people who niggles over pennies (18%?). If the meal was expensive, there were a lot of people at the table, or children in the party, I may tip more. (Children with cheerios are every buffet server's worst nightmare, since buffet servers clean their own stations.)
In terms of automatically adding the gratuity, I think it's a ridiculous practice, and I never did it even when the menu stated it was restaurant policy. I found that most people tipped more than the fifteen percent automatic gratuity anyway (particularly on small tickets, like lunches). And even after being regularly stiffed by huge groups at the buffet, I still believe tipping should be voluntary -- its a tip not a tax.
The interesting thing I noted--which hasn't been addressed too much in this thread--was that the amount tipping seemed to be inversely proportional to the (perceived) socioeconomic status of the students, i.e. the newest, nicest dorm on campus (in which the athletes lived) seemed to house the worst tippers, while the dorm with all the artists and music majors tipped, on average, rather generously. (I was a music major as well, but I certainly didn't know all my customers personally.) My theory on why this happened was that the artists and musicians may well have worked in similar businesses at one time.
Like many others, I leave a buck or two at buffets. As for "sit-down" restaurants, I've tended to double the tax (assuming no alcohol is included in the bill, which I realize messes up things). In Texas, that comes out to around 16.5%; I hope the twenty-percenters in this comment thread wouldn't consider me to be cheap.
My wife and I are tech professionals in the Bay Area. An extra $5 out of our pockets has essentially zero marginal impact on our quality of life, and potentially a large positive impact on the server's. And if the server remembers us next time...
But if the tip is "mandatory" as has been mentioned it is in some places and perhaps more in the future, why isn't it included in the menu price?