Yes, people do it.
It isn't an easy life. You get a tiny apartment and share bedrooms. Parents (more likely parent though) often sleep in the living room. Not all apartments will allow this but enough will that you can find a place. There is enough money for shelter and food, and the cheap cable TV, so that is your entertainment.
It isn't a bad life, but you are limited away from a lot of the things most of us enjoy.
I know people who have done it. I went to college and want my kids to do the same so they don't have to live that life. Unfortunately most in that life don't realize that it wouldn't be hard to get their kids out of it. They are eligible for a lot of programs that the rest of us can't get to take care of the costs, but if you don't realize that the effort of applying yourself is worth it they won't get you out and the cycle repeats.