The smoking policy has been evolving over time, responding to ongoing abuses. As soon as they prohibited smoking within the bowl itself, some (NOT ALL) people continued to try to smoke there even though there were specified areas where it was allowed. It has gotten to a point where enforcement of the rules in place (again due to continued abuse) has taken so much security/police attention away from where it is needed that the Bills have now not only prohibited smoking from all areas, they have actually prohibited bringing tobacco products into the stadium. There's now no grey area. You are caught with tobacco products, you get rid of it (no more "just put it out") or you're gone.
Don't blame the team for the bahavior that forced this drastic action.
Here's a link to the smoking policies of all NFL teams. Buffalo is not the only one that completely prohibits smoking.
http://www.no-smoke.org/pdf/smokingpoliciesNFLstadiums.pdf
The smoking policy comes up at every meeting. It is what it is.