What he can do with his millions is give back to his family, and that's what he prefers to do.

When CNBC Make It asked about the most fun he's had spending, Leno didn't point to anything material. "The funny thing about having some money is you can't really be a big shot in Hollywood every day, because there's so much money here you're not going to impress anybody," he said.

Jay Leno spends a lot on cars: His impressive auto collection consists of more than 100 vehicles, including a McLaren F1 that he bought for $800,000 that is now worth more than $10 million. But buying vehicles isn't his favorite way to spend money — nor is buying fancy clothes or big homes.

"When I go back home and, if I can put a roof on my uncle's house or help out one of the relatives, then when you go to dinner, 'The big meatball is for Jay! Jay gets the big meatball because he paid for the roof!' And then you get the big meatball and you get to sit at the head of the table," said Leno. "It doesn't get any better than that."

Leno, who hosted "The Tonight Show" for 22 years and now hosts CNBC's "Jay Leno's Garage," said he never set out to become a multi-millionaire: "I enjoy working more than I enjoy making money. I like to work hard. I was never someone who was always trying to make a gazillion dollars."

Networks and other venues did end up paying him well — he reportedly earned as much as $30 million a year at the height of his career — but that didn't change the "really conservative" financial philosophy he adopted from his Depression-era parents: "They just frightened me to death, saying, 'You gotta save every penny!' And I'm glad they did."

"So many people get to be the age I'm at now and they've got nothing because they just blew it all," Leno added. "I put my money in a hammock and say, 'You relax. I'm going to go work.' And when I come back, I put some more money in the pile. It sounds ridiculous but, if everything ends tomorrow, I know I'll be fine."

CNBC's " Jay Leno's Garage " airs Thursdays at 10 p.m. ET.

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