Jay Leno, Graham Stephan and Barbara Corcoran can afford most things, but even they have frugal tendencies.
"I have hold-backs," Corcoran tells CNBC Make It, adding: "I think everybody is cheap in some way."
Here's what these millionaires refuse to spend their hard-earned dollars on.
Former "Tonight Show" host Jay Leno loves buying and collecting cars, but you won't catch him spending at a department store. "I'm just not interested in clothes," says the self-made millionaire. "To me, it seems like a complete waste of money. I just want to have enough clothes to cover legally what parts I have to cover."
His financial philosophy has always been "really conservative," he tells CNBC Make It, partly because he had Depression-era parents: "They just frightened me to death, saying, 'You gotta save every penny!' And I'm glad they did."
Even after Leno started making millions, he didn't change his money habits. In fact, he has yet to spend a dime of his "Tonight Show" money.
YouTube millionaire Graham Stephan, who earns up to $220,000 a month, feels strongly about making his coffee at home. "I think the markup of coffee at Starbucks and Coffee Bean and a lot of those places out there is absolutely ridiculous, so I just make it at home for 20 cents," he tells CNBC Make It.
He buys his coffee at Smart & Final, where he can get a large bag for "like half the price" of other grocery stores, he says.
Like Leno, he also doesn't like to shell out a lot of money on clothes: "Designer clothing is one of those things that I will never spend money on. I just don't see the point in spending $700 on Gucci shoes when you could go to Aldo or Call It Spring or H&M and get very similar shoes for one, one-hundredth of the price."
Partly because getting to ride in a plane at all still feels like a privilege, "Shark Tank" star Barbara Corcoran sticks with economy class when it comes to flying: "I'll never spend money on a business class or a first class ticket. Forget about it. I'm always in coach. I just couldn't fathom justifying that."
That said, she tells CNBC Make It, "I have a routine that makes me feel better than everybody in first class."
Corcoran, who made her fortune in real estate, doesn't board a flight without a pre-packed gourmet meal. She brings fresh fruit, fancy cheese, a baguette or croissant and "always a small bottle of wine," she says, "which, of course, you can't bring through security but you can get it at Shake Shack in the airport."
She also packs a colorful, oversized napkin that serves as a tablecloth and her own utensils. "When I sit there and open up my little gourmet meal, I'm telling you, it's much better than anybody's getting up in the business or first class," says Corcoran.
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