Tradesy is an online consignment market, where people can sell designer and luxury goods that they no longer want. The top brands that sell on the site are pretty much what you’d expect: Chanel, Louis Vuitton, Hermès, and Tiffany. Yet brand #3 in their top five is one that you might not expect: Lululemon, an athletic wear company. Are people really that crazy over yoga pants?

Yes. They are. Racked looked into the Lululemon resale market, and discovered an entire hidden world. Instead of getting a discount on yoga pants that someone else has already sweated in, this business is actually about taking merchandise that’s scarce, holding on to it until it’s valuable, and then reselling it.

This works for items that are brand new with tags, but used items retain their value because of the durability the clothes. The company doesn’t condone this secondary market, but at the same time offers limited-edition products and brings different items in different colors into and out of circulation. This makes the items artificially scarce, and therefore valuable to someone.

In an interview, the CEO of Tradesy told Racked that the secondary market for Lululemon gear is something that they hadn’t really anticipated. “We always see markups in rare Chanel bags or vintage Louis Vuitton, so it’s interesting to see it happening with pants that make your butt look good and only retail for $80.”

What kind of markups? How about some rare running shorts that are currently bid up to $1,000 on eBay? Limited-edition leggings with a tie-dyed effect sell for hundreds of dollars.

One flipper describes searching resale values on eBay from the dressing room of her local Lululemon outlet. Yet this flipper, who makes a nice profit simply flipping Lululemon products on eBay, worries that she could end up banned from the company’s stores, just like how Sephora bans suspected makeup resellers from making online purchases.

Inside Lululemon’s Booming Underground Resale Market [Racked]

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