Pinching pennies isn’t just for cash-strapped shoppers. More affluent consumers are looking to save money, and they’ve been a key demographic in propelling the continued blockbuster growth of America’s largest retailer.

Walmart posted another knockout earnings Thursday, reporting a 4.8% year-over-year increase in quarterly revenue to $169.3 billion. Second-quarter sales increased 4.2%, beating analysts’ estimates. The retail giant raised its guidance for the rest of the year from 3% to 4%, expecting sales to increase 3.75% to 4.75% for 2024.

Walmart hasn’t witnessed a weakened consumer that some analysts and investors feared, CEO Doug McMillon said in Thursday’s earnings call. Shoppers are going to Walmart in droves—regardless of how much money they make.

“We’re also seeing higher engagement across income cohorts, with upper-income households continuing to account for the majority of gains, even while we grow sales and share among middle- and lower-income households,” McMillon said.

Walmart reported increases in its health and wellness category and Sam’s Club membership across income levels as well. It’s a continuation of a pattern Walmart noticed earlier this year of higher-income consumers driving sales growth.

The company has benefited from an overall increase in consumer spending recently. Navigating tentatively cooling inflation and a slowing job market, consumers are less willing to shell out on discretionary goods and big homegoods purchases. They are, however, spending big on bargain goods and groceries.

It’s these types of products that have largely driven Walmart’s growth, led by its Bettergoods private-label brand, released earlier this year. With bright packaging and a host of plant-based and premium products, the label has appealed to higher-income households looking for affordable healthier and more premium products. Higher-income consumers are actually more likely to consider buying from Walmart than other retailers like Whole Foods and Trader Joes, according to May data from market research firm YouGov.

Affluent shoppers are also more likely to shop online and have their groceries delivered, a trend that has coincided with Walmart’s burgeoning e-commerce business, which grew 21% globally this quarter. During this period, weekly active online customers increased 20%, and store-fulfilled delivery rocketed 50% as Walmart promised speedy deliveries between one and three hours.

Higher-income consumers flocking to Walmart is good news for the retailer. But it’s also a reason for all retailers—even the high-flying Walmart—to remain cautious about consumer spending. Though Walmart has weathered tough economic times—as well as volatility from geopolitical events like the U.S. election—CFO John David Rainey told analysts the company is “not immune” to economic tensions, and neither are consumers.

“When money is tight, people react—even high-end consumers react,” former Walmart U.S. CEO Bill Simon said in a CNBC Fast Money interview in May.

Other discount retailers have also noticed the trend among wealthier shoppers. Dollar General CEO Todd Vasos told analysts in June its higher-income consumers continue to focus on bargain brands, a symptom of not only cautious consumption, but of shoppers testing the waters of where to save and splurge.

“[W]hat we’re seeing is that the next cohort and the one above that—so, let’s call it middle- to upper-middle-income and then in some of the upper-income stratas—we’re seeing the trade-down still come in,” Vasos said.

While affluent customers have helped Walmart soar even when the public at large largely remains trepidacious, it may be hard for the retailer to retain this key demographic in the long run, Simon said. Walmart has improved its shopping experience with store renovations, appealing own-brand product lines, and convenience shopping, but it’s not the premium shopping experience wealthier consumers will look for as economic worries wane, he argued.

“As the economic challenges abate…service will become more important than convenience and price,” he said. “And we’ll see a shift back of some of the consumers.”