I don't see a problem with people moving back home if there's a reason (job loss, divorce, spouse dies, etc). It can be a good way to save some $$ and get some emotional support from the family.
I myself couldn't have done it. My parents' house isn't set up with a separate entrance, plus there's the whole "their house, their rules" thing - to this day they look at me and see an eight-year-old.
Also, I'm married and own my home.