Here are the quirky, frugal habits of seven other millionaires and billionaires.
New England Patriots tight end Rob Gronkowski, who recently announced that he's retiring from football at age 29, is frugal when it comes to his wardrobe. "My 'broke habit' still is my clothing and shoes," he told Maverick Carter on a 2018 episode of UNINTERRUPTED's "Kneading Dough." "If I like the clothing, if I like the shoes, I'll wear those shoes and I'll wear that clothing down to the rags."
He'll sometimes wear a favorite pair of jeans "seven days straight," he said, adding: "I make sure I throw them in the washer, like, Day 3."
For more than 50 years, the CEO of Berkshire Hathaway has reportedly been enjoying the same breakfast every morning, and it never costs more than $4. Depending on how he's feeling, the self-made billionaire orders one of three items at McDonald's: two sausage patties, which costs the least; a sausage, egg and cheese; or a bacon, egg and cheese, which is the most expensive at just over $3.
He also lives in the same home he bought in 1958.
Olympic gold medalist Simone Biles doesn't take her success, or the money she's earned from it, for granted. In fact, the 22-year-old gymnast has "a fear of going broke," she recalls on an episode of "Kneading Dough" with Maverick Carter.
It keeps her careful. She even challenges herself to go days without spending any money, she tells Carter: "And then, of course, my gas light come on so I have to go get gas."
Besides the necessities, as well as the occasional trip to Subway, she says, "I never really swipe the [credit] card."
Baseball star Giancarlo Stanton signed a record-setting $325 million contract with the Marlins in 2014. And between his salary and endorsements, Stanton, who was traded to the Yankees in 2017, earned $28.2 million last year.
That's partly because "you don't need money to have style," he says. "I go to T.J. Maxx and Marshalls."
Comedian and former host of NBC's "The Tonight Show" Jay Leno plays it safe when it comes to money. From the moment he entered the working world, "I always had two incomes," he tells CNBC Make It. "I'd bank one and I'd spend one." And he made sure to spend the smaller amount.
Leno continued relying on this strategy even after he started hosting "The Tonight Show" in 1992, which reportedly earned him as much as $30 million a year.
"When I got 'The Tonight Show,' I always made sure I did 150 [comedy show] gigs a year so I never had to touch the principal," Leno says. "I've never touched a dime of my 'Tonight Show' money. Ever."
"You do something called resoling and re-heeling," he told the New York Post in 2010. "You don't have to throw them away and get new ones, you can just use the old ones."
Nora Lum, better known as Awkwafina, appeared in two major motion pictures in 2018: "Ocean's 8" and "Crazy Rich Asians." Mostly thanks to those big roles, today she has an estimated net worth in the millions.
Still, Lum says she's careful with her money. "I don't splurge on literally anything," she tells guest host Lisa Ling on an episode of "Death, Sex & Money." And she's thrifty when it comes to clothes: "I'm literally wearing Target pants."
The 29-year-old still lives in the first place she moved into after college, a railroad apartment in Brooklyn, New York, that she found through a friend. When she first moved in, she rented one room for just $500 a month.
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