Let's make it less complicated than you suggest and simply ask:
Why should someone work for a place like Aston at all?

Life is more fun without them; very simple.

Having no real experience with a University, I can't really give you a good reason why Aston is better than a good Uni. All I can say is that I've met the VP, my regional direct, the training VP/managers and they're all nice people who do look out for us. They aren't trying to scam people at all.

I work at a franchise. The place I work at is ok... Could be better but there are many other schools in my city that have shown I don't have it bad. Even the University here screws up. They asked 6 people from England to come over and sign a contract for August. This was mid-July I think. They came over, a week later the Uni said they cancelled the classes for August and that they'd have to fend for themselves until September where they could guarantee them work. 2 Flew back to England, and now the school has to find another 2 teachers or something.

My only point is you can find a good Aston if you look for one. Corporate ones are good, I have some friends who've left the franchised ones for them and they're happy.

Life is the same regardless of whether or not Aston exists. Life is only any less fun for the individual who gets stuck at a bad Aston, but then he'd be equally capable of getting stuck at any other bad place.