Insulting Fat People at a Buffet

At buffets I allow myself two trips, but I usually avoid them except quarterly trips to a favorite Asian buffet. I once had the opposite of this happen at a friend's wedding dinner, at a Chinese Buffet, the owner of the restaurants, came up to me and said, "You don't like my food, you only took two trips!"
Anyhow I know sometimes if you are fat, people can make comments if you eat the wrong thing in public.