I was watching The Big Bang Theory the other day (I watch it pretty much incessantly; I think I've become co-dependent). Many scenes take place in the university cafeteria and in Leonard's apartment during dinner. I noticed that the actors seldom eat anything. If you recall in the Godfather, in the wedding reception scene where Michael and Kay are talking, Michael seems to masticate his Lasagna with his fork, but never eats any of it. I guess when you're shooting the 7th take of a scene, eating is not high on your list.