Our first home game last year was against Missouri. I paid an exorbitant amount of money for really great seats for my girl and me. After 3 straight TD's by Mizzou and 3 straight 3-and-outs by us, I calmly gathered our stuff and we went to a mexican restaurant and got bombed on margaritas.
I think when someone pays money to go see a game, essentially blowing a weekend that could be committed to much more accessible pursuits, and like most Southern males, has their vicarious ego crushed on top of the expenses and effort that goes into attending a game, any and all reactions are acceptable.
The team one roots for will not perform at a higher level just because so-and-so is sitting in the stands, so it's a positive sum game for all parties involved. The school gets their money and the fan gets to express their feelings. Posturing that people should stick around until the bitter end need to come down from their cross and realize that a football game is entertainment. Just like Wayan's Brothers film watchers, when OM craps the bed, I'm headed for higher ground.
If you pay money to see a game, you have the by-God right to get up, curse anyone within earshot, and sullenly flee.