US Blues
Headphoneus Supremus
The only NFL game I have attended was the Oakland Raiders v Seattle Seahawks, at the stadium in Oakland (can't recall its name) back in 2000. It's a long trip to go to games when you live in Australia. What struck me the most was the tailgate parties before the game - totally amazing.
That is the Oakland-Alameda County Stadium. Pregame tailgating at US football games, pro and college, is both an art form and a cultural phenomenon.
PS- I am surprised you saw no evidence of violence in the stands among Raider fans in Oakland, they were renowned for that.