With an estimated net worth of $400 million, Kevin O’Leary could afford to never cook, clean, or grocery shop for himself ever again. But the Canadian businessman and Shark Tank investor isn’t one to pass up financial savings—no matter how small.

“I’m always looking for a great deal, that’s why I’m in Walmart,” he said in a recent Instagram video. “You know those fantastic black jeans I’m always wearing? That’s right—Walmart special, 29 smackaroos. That’s how you save dough.”

The 72-year-old added that his wife sent him to the store to buy some essentials, including batteries, butter, paper towels, and OxiClean laundry spray. But O’Leary wasn’t about to waste the opportunity to hunt for a saved buck.

“I want to save dough when it comes to paper towels. Check it out. Bounty—12+ rolls is like 18 small rolls—I’m going plus,” he said with a smirk.

O’Leary, who owns multimillion-dollar homes in Florida, Massachusetts, and Toronto, has made the point to shop at Walmart on numerous occasions—long arguing that there’s no reason to pay more for everyday essentials when a cheaper option will do. 

Plus, as O’Leary sees it, there’s no guarantee the money you spend today will still be there when you need it.

“I hate wasting money,” O’Leary told CNBC in 2021 after a Walmart run went viral. “I just don’t get why you would do that. It’s so hard to make it in the first place.”

From Warren Buffett to Scale AI’s Lucy Guo—even billionaires still look for ways to save

O’Leary is not alone among the ultrawealthy in keeping a frugal streak. Some of the world’s richest people have continued to hunt for bargains and avoid spending more than they need to, even as their fortunes have grown.

Warren Buffett, whose net worth currently sits at about $144 billion, has long embraced a famously frugal lifestyle. The 95-year-old still lives in the same five-bed, two-and-a-half-bath home in Omaha, Nebraska, that he purchased in 1958 for $31,500. Today, the house is worth over $1.3 million.

He also famously used to stop at McDonald’s on his way to the Berkshire Hathaway office—and let the stock market dictate his order. When markets were down, he’d spend $2.61 on two sausage patties. On better days, he’d splurge $3.17 on a bacon, egg, and cheese biscuit, according to a 2017 HBO documentary.

Ikea’s late billionaire founder Ingvar Kamprad had a similar love for savings. Despite at one time having an estimated $58.7 billion fortune, Kamprad bought second-hand clothes and drove an old Volvo.

“I don’t think I’m wearing anything that wasn’t bought at a flea market,” Kamprad said in a 2016 documentary on Sweden’s TV4. “I want to set a good example.”

Kamprad also continued working at Ikea until he was 87, more than three decades after he became a billionaire. He died in 2018 at 91.

One of the newest members of the billionaire club, Scale AI cofounder Lucy Guo, is a more recent example of someone whose spending habits have remained relatively modest as her fortune has soared. The 31-year-old has long embraced the FIRE (financially independent, retire early) movement by going to extremes to save money, including buying discounted clothing, skateboarding to work, and booking flights she would later cancel so she could eat for free in American Express airport lounges.

“Everything I wear is free or from Shein…Some of them aren’t going to be that great quality, but there’s always like two pieces or so that really work out, and I just wear them every day,” the billionaire founder previously told Fortune. “I still literally buy buy-one, get-one-free on Uber Eats.”

This story was originally featured on Fortune.com