After Auburn finished off a 26-14 over No. 1 Alabama in the Iron Bowl, the fans were damn excited. And rightfully so; beating your rival is huge, beating Alabama is huge, and the win clinched the SEC West title, which is huge.
When fans are excited, they storm the field. It's what they do. But that's now against the rules—the SEC apparently instituted a rule in 2004 that fines universities if their fans storm the field. This was Auburn's third offense, which resulted in a $250,000 fine.
I get this on both sides. Storming the court/field is undoubtedly dangerous, so it's hard to argue with the fine.