It's a ridiculous endeavor. You can't stop it.
There's nothing that's going to be a DISINCENTIVE to the fans. The school having to pay a million dollar fine? So what? They sold 80,000 to 100,000 tickets to the game, they can easily cover the million bucks.
And you can't stop it from happening with ropes and barricades -- There ARE barricades between the field and the seats. They're jumping over them.
And uniformed law enforcement isn't gonna work either. There ARE uniformed law enforcement at every game (definitely by the visiting team at every game for their safety and elsewhere, too).
But if TWENTY THOUSAND OR MORE people start coming down, a thousand cops are still out-numbered 20 to 1.
If they WANT to storm, they're storming.
The only way to make them NOT WANT TO is really mockery. Players saying "I hope our fans never storm the field. We're SUPPOSED to win at home. Oh, you beat #1? That's not an achievement. The goal is to BE #1." That kind of thing.