I'd rather go off on a usher. After all they're the ones that set the ticket sale capacity, control the refund policy, and all of that stuff.
I think it's also locals not knowing/expecting what's coming. GA tickets are becoming common in MLB stadiums and some other pro sports, in addition to their popularity in college sports. Maybe sell a fixed number of GA tickets and then specifically sell standing room only tickets. GA tells me "if you want a good seat, come early", SRO tells me "I might be watching the back of somebody's head for half the game if I arrive late".