For me, it was a preference. I moved out when I was 16 for the most part, and officially moved out when I was 18. I started working full-time through the summer and weekends through the school year when I was 14. Well, that was when I started working legally. Had stuff like under the table restaurant jobs when I was 9, sold my artwork, mowed lawns, etc. I just couldn't wait to move out. I was not privileged in any real sense, but when I was 18 I went to college and rented my own house. I lived off earnings from previous summer. No cable- didn't care. No high speed internet- different times. Car was paid for with cash. Car insurance paid yearly upfront. Few expenses.
Once I moved out, I never wanted to move back in. I briefly went back for a summer when I was 23. I had made the mistake of moving in and moving away with a batshit crazy sexy chick, and found my life in temporary ruin. Moved back "home" for one Summer, saved all my money from working 60-hr weeks and moved back out for good.
Regardless of the economy (I supported myself on low-end work) and anything else, I would just WANT to NOT live with my parents so bad that nothing could keep me there. If other people and their parents are cool with them living at home forever, doesn't bother me any.