It's pretty obvious that most of them start out still living with their parents based on what the houses look like. Even if they aren't nice places, it's always more fully furnished and larger than a 20 year old obese headcase would have to show for themselves. Not to mention, half look like they're still in the bedroom they grew up in.
When you're in your early 20s and have no prospects, but all of a sudden some money is available, moving out is about the first thing anyone chooses to do. I remember in college all my CC/non college friends who were floating around were always coming up with some roommate scheme to move out, which panned out for like 6 months at a time.