Pffft. My "not good for me" friends are my cycling friends. Cyclocrossers in this area (by and large) are a bunch of drunks, and I can't drink. I'm the only guy on the team who has a dedicated ginger-ale hand-up dude on the sidelines.
But hanging out with them keeps me honest and in shape. When everyone knows you don't drink (and respects that fact) they make sure you don't. And by riding with this bunch of maniacs every weekend (including a current World Champion) and keeping off the empty calories, I'm dropping weight like a madman and I'll hit race weight in time for this next round of kit orders (and I need to go a size or two smaller.)