A couple of comments on this.
First, many of those 25k students are adult, evening, and non-traditional students. UNO has, however, recently introduced some on-campus dorms as the campus has expanded into some of the former AK-SAR-BEN property.
Second, the decision to remain with DII football was made before Trev Alberts took over as AD last year. Don't be surprised to see him push to bump the program up in the next several years. He has hinted that there is room for UNO to be a DI player in the state as long as they don't try to challenge the pecking order that puts Lincoln on top.
The problem is that the hockey program provided a huge financial boost when it was first introduced. The luster has worn off and it is now closer to break even status if not a money loser. If Alberts can be successful in his attempt to increase fundraising, look for football to be the beneficiary.