That's the rule in Alabama, and it's apparently being enforced against a wine that bears this label:

Seems pretty clearly unconstitutional; though commercial advertising (which would include product labels) is less protected by the First Amendment than most other speech, it generally can't be restricted on the grounds that it's offensive. Nor do I see any reason why nudity would be any different. Such depictions of nudity are generally constitutionally protected (see Erznoznik v. City of Jacksonville), and would presumably be no less protected on commercial advertising.

It's possible that some material that is constitutionally protected against obscenity prosecutions might still be so sexually explicit that it can't be displayed where unwilling viewers — and especially children — might see it. But I doubt that the picture above would qualify as "so sexually explicit," especially given Erznoznik's holding that mere nudity can't be restricted on such grounds. And in any case I see no constitutionally sufficient justification for banning such material on offensive grounds on alcohol advertising but not on other forms of advertising.

Thanks to Graham Simms and Dr. Vino for the pointer.