A lot of grads come from money and move right in family "job" or get jobs form family connections.
Remember this guy?
"Michael Hess isn’t an ordinary member of Harvard Business School’s Class of 2013. After all, he’s a legacy graduate of both HBS and Harvard University and the son of John Hess whose net worth is estimated at north of $600 million. His father is chairman and CEO of the Hess Corp. which was founded by Michael’s grandfather, Leon Hess."
http://poetsandquants.com/2013/09/10/scenes-from-harvards-super-rich-mbas/
There are a lot more very very wealth people going to these schools. If a person graduates and is given a billion dollar property portfolio in New York, it really mores the numbers. It's one of the reason to go to these universities...your frat brothers father gives you a small piece of the deal but could be worth millions.