Quite the understatement. Harvard/Yale/Stanford don't do merit-aid scholarships so you would have to be super poor to get some financial aid and even then isn't likely to be a full-ride.
Doesn't Stanford offer free tuition for students of parents making "less than $125,000 annually"? (previously $100,000). However, I'm not sure if this only applies to undergrads. Just something to check out.
Stanford, Harvard, Chicago (Booth) and Penn (Wharton) are king. The most elite investment banks and private equity firms to refer these schools to others, as they are the best of the best.