(Bloomberg) -- When Holli, a 33-year-old mother of six, started collecting Stanley cups in 2019, she was part of a small but dedicated fan club. The company would occasionally release new colors, and Holli joined Facebook groups to trade cups with fellow enthusiasts. At one point, her Arizona home contained more than 200 Stanleys, a collection that earned her millions of views on TikTok. 

Fast forward four years and Holli’s Stanley interest is starting to ebb. Limited releases, once sporadic enough to be exciting, are increasingly common. The Facebook groups are bursting with members, and the resale market is more and more saturated. After donating a slew of unused Stanleys to friends, family and her church, Holli says her collection is now down to 112. 

“When people talk about the overconsumption … it’s the business that’s driving this,” says Holli, who declined to share her last name. “It’s going to have to start with them to slow this down.” 

“Them,” in this case, is Stanley, the company behind the Quencher H20 Flowstate Tumbler, a 45-ounce (1.3-liter) metal tumbler known as “the Stanley.” The $45 reusable cup is part utility, part status symbol and part internet craze: There are limited-color drops, influencer testimonials and collaborations with major brands. When Stanley and Starbucks teamed up on a pink tumbler for Valentine’s Day, Target customers camped out to snag one, sometimes coming to blows. Those cups now sell for more than $300 on eBay. 

On its face, the Stanley craze seems like an answer to a vexing issue: Non-reusable water bottles generate as much as 200 million tons of carbon dioxide equivalent per year, plus plenty of plastic waste. A big part of the Stanley ethos is that this is a cup built to last: One woman attracted 95 million views on TikTok when her Stanley survived a car fire with un-melted ice still inside it. 

In practice, though, the Stanley has become an icon of overconsumption. Metal tumblers, tote bags, steel straws and other reusable goods are often marketed as a way to displace single-use alternatives and cut greenhouse gas emissions. But that calculus only works if the reusable product is actually reused, and it definitely doesn’t work if the product is never used at all. 

“These companies selling water bottles and flasks that are not plastic can really tap into that mindset of, ‘this is a healthy product that, if you can reuse it endlessly, the impact is far less on the environment and on people’s health,’” says Erica Cirino, communications manager at the advocacy group Plastic Pollution Coalition. “You’re selling a solution, but it’s not a solution if you’re selling a bajillion of them that aren't going to ever be sipped out of.”

While the Stanley brand has been around for 110 years, the modern Stanley story starts in 2017. That’s when The Buy Guide, a popular women’s blog, first posted about the cup. Up to that point, it had been marketed as camping gear for men. The Quencher gained popularity through social media influencers and word of mouth among moms on the go, but not enough to grab the attention of Stanley. By 2019, rumors were swirling that the company planned to discontinue its tumbler, so The Buy Guide’s founders bought 10,000 cups wholesale and started selling them. Within five days, they sold 5,000. An hour after they posted the second 5,000, they sold out. 

That success piqued Stanley’s interest, and The Buy Guide helped convince the company to keep its cup around — and to start marketing it to women. By 2020, the tumbler had taken on a life of its own. Social media influencers showed off their collections online, in display cases housing dozens of different cups. A swath of accessories — straw covers, carrying cases, charms and even snack trays — emerged for those looking to trick out their tumblers, and TikTok’s Stanley cup hashtag filled with people showing off Stanleys that had never been used. The company’s revenue jumped from $70 million in 2019 to more than $750 million last year. 

The Buy Guide co-founder Ashlee LeSueur, 44, says that Stanley and the site are now in a “financially and professionally beneficial partnership,” with perks that include her receiving a new cup with every color drop. Pre-Stanley, LeSueur was buying cases of plastic, single-use water bottles for her family. Today, she alternates between three Stanleys, and her family no longer buys plastic. 

“It has completely changed the lifestyle in my home,” says LeSueur, who lives in Carlsbad, California. “Plus, it’s way cuter, and you’re doing something good for the environment.”  

Houston resident Amina Malikova made the single-use-to-Stanley conversion in May 2023. Today, the 24-year-old owns 13 Stanleys (her favorite is a “Flamingo Pink” version) and has racked up almost 5 million views on her Stanley TikTok videos. She makes a habit of matching a cup to her outfit and shares her collection with the seven family members who live with her. 

“We see all the time that [our customer] wants her Quencher to match her fit, her nail polish, her car, her mood, her kitchen,” Stanley President Terence Reilly told CNBC in December. “We’re serving her where she wants the product.”

Stanley and its competitors — Hydro Flask, YETI, S’well and CamelBak also make reusable bottles and cups — are one answer to bottled water. The world produces over 450 million tons of plastic each year, none of which ever fully disappears. Only about 1% of rigid plastics are recycled, and plastic exposure has been linked to cancer, birth defects and lung disease. One recent study found that an average 1-liter bottle of water contains 240,000 nanoplastics small enough to enter the human body.

“Getting people to switch from single-use water bottles to reusable — that cultural shift would be very positive for the environment,” says Greg Keoleian, co-director at the University of Michigan Center for Sustainable Systems. “I don’t think everybody's going to have this huge collection.”

But making a reusable metal tumbler has its own carbon footprint. Steel production is responsible for over 7% of greenhouse gas emissions globally. That means a reusable container needs to have multiple uses to be environmentally effective, and should ideally be made with recycled materials. While little data exists on those trade-offs for bottled water specifically, one 2010 report commissioned by Nestlé found that a reusable bottle would need to be used 10 to 20 times, depending on size and material, to offset the components and energy required to make it.  

Stanley isn’t unaware of those caveats. A Seattle-based brand under the umbrella of The HAVI Group, Stanley doesn’t break out the carbon footprint of its tumblers. But it does say that the Quencher is made with 90% recycled stainless steel. Last year, Stanley pledged that at least 50% of its products would be produced with recycled stainless steel by 2025, a goal the company said in a statement it expects to meet early. 

According to Stanley’s 2023 impact report, 23% of its products are currently made with recycled stainless steel. The company is also working with manufacturers to expand its use of other recycled materials and it’s working to source renewable energy. In 2022, Stanley attributed 94% of its emissions to the production and shipping of its coolers, lunch boxes and camp cookware. 

What Stanley doesn’t yet offer is a buyback or recycling program for cups at the end of their lifecycle. Hydro Flask has a trade-in program for its old bottles, and separates the recycled materials. YETI offers a recycling program, though just for its Rambler tumbler and the service is only available in-store. But even those sustainability efforts need to scale up quickly to keep pace with sales. 

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