i'm not sure if it sells out every year or not, I tend to think not. But there is always a very large, fun, and well behaved crowd of Bills fans young and old there with fireworks after the game. This year should be interesting as I'm thinking a fair amount of the people will be Steeler fans.
Say what you will about Brandon, but between training camp and the kids day game he is certainly doing a great job grooming the next generation of Bills fans. Not an easy task given the adult nature of regular season games.