I have an extremely picky co-worker. She won't eat veggies of any sort, and pretty much only likes pasta, chicken fingers, and cheeseburgers from one particular place but not from anywhere else. When we have a group lunch, or a work related lunch, we all end up limited by the very few places she will eat. Even when it's someone else's birthday lunch. I'm all for telling her just to suck it up, try something new, or just don't go, but most of the other people will say "Ohh, it would be MEAN to exclude her/tell her she just has to deal with it".
It's very frustrating sometimes.