The Tollner-hating Trojan fans aren't in love with their team, but with themselves. Even if they are correct that Tollner is USC's only obstacle to greatness, they disgraced their school when their boos prevented Tollner from fulfilling the traditional obligation of introducing his seniors to the crowd after the final game.
Didn't they realize that in their lust to crucify the coach they publicly humiliated the team they profess to adore? Of course they didn't. They were too busy leeching off past glory to understand that their team had played a great game, lost and needed fan support more than ever.