It depends if they want to or not. I could have probably driven myself to get to Yale or Harvard, but I would rather not owe $150k when I get out of school. Not to mention my grades kind of went down a bit after my 1st year in highschool...about when I got interested in MB's.
I think schools such as those are only good to make friends! If you join clubs and make friends very likely you will have some powerfull connections in the future. Look at the Skull and Bones club Bush is a member off. I wouldn't want to spend 5 years at Yale meeting no one important and getting out with an education degree and $100k in loans. But if that is what you want to do, whatever makes you happy. I can and do go to a state school and will get a perfectly usefull degree for about $5k a year.