My oldest high school friend earned his PhD and is now on tenure track at a branch of UT. He paid for it all by working like a demon. He had a good chunk of savings when he graduated. He is the most productive person I have ever met. This is including raising two children and GMing several multi-year pen-and-paper RPG campaigns. He's smart enough, but not a mad super-genius. He's done it all with an inhuman work ethic.
A 19-year-old girl I have known since she was in her mother's womb danced (read: stripped) her way through college, graduated with a 4.0 average too early for her nursing program (they won't take her 'til she's twenty). So she has a year off, with no debt. New car. She already makes as much as I do, and I'm a software architect with a decent job.
I have another friend with four bachelor's degrees, is a professional dancer, masseur and piercer. He owes over $100k in school debt, mostly to the federal government, a bit to private parties. He earns his living doing amazing custom carpentry. Never plans on paying the federal stuff back, he can't, realistically, unless he devotes a good chunk of his life to it, and you only get one.