Not pertaining to anyone in particular, but like you, the 'rich' people I know are frugal, however, they also don't complain/worry when they do need to spend money. They are thankful they have it to spend.
One couple I have in mind have a child that just finished college at a very expensive school.
They were not qualified to get student loans (their son wasn't) and they weren't qualified to get parent loans. I don't know many 'rich' people who can get the loans. They have the money to pay, so it's expected they pay. Their son still got merit grants, but no loans
While they may look for the best place to get their sons books, it's not a hardship for them to pay what they have to pay. I'm sure they have a nice nestegg (just bought a wonderful second home in a really nice vacation area), just judging by how very generous they are to our cat rescue.
You are correct, many rich people live below their means..I imagine it's how they stay rich..but they usually don't need to take out loans to pay what they owe, unless taking out the loan is less interest than the money they are earning on their savings.