I believe it is a lot of things.
The most vocal people who say they wont go to a game because the atmosphere are the same people who wouldnt go anyway. It reminds me of the non-hockey fans who feel the need to criticize fighting in hockey as if they would watch it. Drama queens like Schopp and the Bulldog.
It may be slightly worse. But its the product of the team IMO. When I go to concerts, I will have a bunch to drink, whatever, have fun... but if its an act I care about and want to preserve the memories... and not have to go to the bathroom... I will limit myself to 1 or 2 drinks all day.
I can see this being true with the Bills games. If its a playoff game, or they are an exciting team gunning for New England... I would likely lay off and take it all in.