Gen Z's latest hot club is Costco

• Some Gen Z shoppers are trying to save money by shopping at Costco and Sam's Club.
• They're sharing bulk groceries and membership cards with roommates and family.

One of Gen Z's biggest tools for fighting persistently high food prices: Sharing a big cart of groceries — and potentially a membership card — from Costco or Sam's Club with roommates or family.

The young shoppers, many of whom are buying groceries on their own for the first time as college students or entry-level professionals, are buying huge bags of flour, packs of meat, and other bulk groceries, then splitting them with others in their social circles to save money, the Wall Street Journal reported on Friday.

It's one way to save money as Americans are still spending a historically large share of their income on food.

For warehouse retailers, Gen Z represents a fast-growing source of new memberships. The number of Sam's Club members age 27 and younger grew by 63% over the last two years, the Walmart-owned chain told the Journal.

One shopper who spoke to the Journal, recent University of Illinois Urbana-Champaign graduate Devak Nanda, said that he and his roommate walked 20 minutes each way to Costco to stock up. They used a wheeled cart to get groceries back to their apartment.

Other Gen Z and Millennials quoted in the Journal's article say that they split large packs of food with friends and family — even those that they don't live with — to get the savings of shopping at the wholesale retailers without having to store all of the food themselves.

For some, though, the tactic backfires. Nanda told the Journal that he eventually realized shopping at Costco wasn't actually saving him and his roommates any money after he did the math.

Costco and Sam's Club might be happy for the new customers, but they're likely less eager about those who share membership cards to make the purchases.

For example, Costco employees have started asking shoppers to see the photo on their membership card when they approach self-checkout to cut down on people sharing memberships.

Wholesale retailers like Costco and Sam's Club have long appealed to consumers who shop for big families or parties. But some single people say a Costco membership makes sense for them thanks to benefits like savings on gas.

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