If I understand correctly, some people UAB pretended they were going to do just that initially, then ended up making the jump to the FBS. They never had any business doing that, and that's the main issue here. They overreached, they overspent, and there was no necessity to do that, nor support to warrant that.
Alabama A&M spends just over 7 million a year on their athletic department. That includes a FCS football program. They spend less than half as much, in total, as UAB loses annually. There's no real excuse for that. If UAB wanted to run a FCS program responsibly, without delusions, I'd have no problem with that. But, their goal from the start didn't appear to be merely having a football program. They seemed to feel entitled to more than that.