I think most young people that have not lived on their own grossly underestimate how much it costs to feed a person. That's the cost that all kids overlook when first moving, myself included. You're like, "It can't be that much - burgers are just 99 cents at McDonald's! So food is cheap! Heck, my parents buy food all the time!"
That's not including the other costs that add up, like toiletries, paper napkins/towels, laundry, etc. Utilities, especially in California, are horrendously expensive. I pay more in fees and taxes on utilities than I do for actual energy charges.
So yeah, a parent who gives a kid a free place to sleep and eat is probably the best gift a parent could give for someone who will be going to college.
I think the most immature comment made by an 18-year-old kid goes to my brother, though. He worked during the entire summer because he wanted a car, which my mother financed for him and got insurance for (he has to pay it off). When he learned he would have to work during the school year because of the insurance costs and to prepare for the impending tuition costs, he said, "WHAT? I JUST WORKED THREE STRAIGHT MONTHS! I WANT TO TAKE A BREAK!"

I should call my landlord and be like, "Dude, I know you like money - but I really need a break right now. I worked for like three or four months. That's straight. Not even vacation time, man. I'm practically a slave!"
WELCOME TO EARF.