1. The rules on standing are like the rules on obscenity: you know it when you see it. Opening kickoff, big third/fourth down plays on D, scores, great plays, etc. Other than that, people should just sit down, okay? No need to be an arsch to people behind you.
2. You hit it on the head. Go to a private lot. We have always gone to one on California Road and we can stay as late as we want. Plus if need be, we can get out a lot faster than people who've parked in the stadium lots.
3. If it's a new NFL rule, then it's a new NFL rule and the Bills can't do anything about it. My guess is that the league sees those walls as prime advertising space.