What's behind the Stanley cup craze?

The craze has prompted long lines outside of Target stores in the dead of night. Ugly fights have broken out. Shouting matches have erupted. All this hubbub over Stanley cups.

No, not the Stanley Cup awarded to the National Hockey League champion. These are the insulated steel tumblers sold at Target and Starbucks.

Collectors and sellers of the tumblers suggest that the craze has been fueled by the manufacturer's marketing strategy, the collaboration with popular companies like Starbucks, the designer colors and a sense that ownership conveys status and exclusivity.

Influencers on TikTok and other platforms have contributed to the mania by posting catchy videos of the tumblers.

But what likely sparked the latest viral popularity was the November TikTok video of a woman's car that caught fire; her Stanley cup not only survived, but it kept her beverage cold. The video has had nearly 94 million views. In response, the Stanley company offered to replace not only the cup but her car.

Stanley insulated cups are not new, having been invented by William Stanley Jr. in 1913. But with a dedicated fan base on TikTok, various styles and prices ranging from $20 for a 14-ounce cup to $60 for a 64-ounce version, anything Stanley is hard to come by.

The most sought-after Stanley cups are the Winter Pink Starbucks collaboration. The cups are fetching upward of $400 on the resell market, according to EBay auctions.

Also popular are Cosmic Pink or Target Red, featured in Target's "Galentine" collection released Dec. 31, which swiftly sold out online and in stores. On EBay, they are selling for nearly $100.

A recent viral TikTok shows a crowd rushing to secure a pair, prompting staff to issue warnings about the per-person limit. The video has garnered 20 million views, and the hashtag StanleyTumbler has accumulated more than 1 billion impressions.

Los Angeles resident Ubaldo Rene Rodas was introduced to the Stanley trend by his younger sisters, who sent him TikTok videos of people discussing the cups, showing them off and even engaging in fights during sales drops. He attributes the craze partly to the limited availability, which makes the cups something of a collectible.

Rodas quickly became a reseller, taking advantage of the surging demand. He listed both versions of the limited-edition pink Galentine cups at $100 each on the Facebook Marketplace, marked up from the original price of $45.

After a recent collaboration between Stanley and country music star Lainey Wilson sold well, Danielle Williams, a reseller, hopped on the trend and started paying closer attention to the market. She has priced the cups at $90 to $110. She said they project a sense of status, like an exclusive club.

Williams secured the cups on Target's website, avoiding the overnight lines outside. She said it seemed as though the people camping out were "working harder, not smarter."

Since joining the craze, she has sold nearly 50 cups and has no plans to stop.

"I just hope the hype train lasts on these Stanleys, and they don't fizzle out like other trendy items," Williams said.