In my experience in the restaurant business (which generally did not involve fine dining establishments) I saw plenty of people who were willing to do this sort of stuff. But as Joseph says, anyone getting caught was fired on the spot. The ones who thought they could get away with it usually did not last long at all.
Letterman asked Zevon if his condition had taught him anything about life and death. ''How much you're supposed to enjoy every sandwich,'' Zevon answered. (From a 2003 NYTimes article on Zevon by Jon Pareles.)