Would it really be so hard to arrainge to hold at campus, given past experience to hold it. I mean it's mainly setting up chairs and a stage, right?
Is it maybe cost, and maybe a high deposit for Anaheim Stadium, that the school could not get back, maybe it's as simple as they don't want to eat $100k + or so they've committed to? If so, just say so if it's really an economics decision. I think students could accept that.
Just 'logistics' is code word for laziness often in my experience.
I mean if nothing else hold a series of Department ceremonies on campus at least, just do it.