Never thought of it from this perspective.
And for that matter, is there student seating for baseball and softball? It would kind of suck to force students to buy tickets to games they don't have access to.
Maybe a cafeteria plan, $value based per game, that is assessed on an individual basis..
6 football tickets = $60
15 basketball tickets = $75
20 baseball tickets = $100
30 softball tickets = $150
Or a single assessment for all sports of $300.
If you can get at least 5000 students to participate, at least you're talking $300,000.