I often want smaller "sample" sizes of food and since I was taught to "only take what you will eat" I would guess that I may have done "breaking off a piece behavior, too, over the years. Your post has reminded me that perhaps "cutting off a piece " would be more polite and hygienic. As a hostess, maybe serving some mini-helpings along the side of some items would be an option. I think I'll try offering that the next time I have serve a buffet .