The Okie State fans rushing the field is the EXACT reason why no unauthorized individuals are allowed on the field in Austin. If you're on the field and you're not supposed to be, you can be guaranteed you'll get a night stick (or tazer

) to the face by a state trooper. They don't play around.
There's actually some pretty stiff collegiate penalties if a student is caught on the field who shouldn't be there. Academic probation for a semester or two depending on what they do.