On any given Thursday, thousands of people can be spotted swarming the corner of Rosewood and North Fairfax avenues in West Hollywood. It’s not surprising, though, if you know that this Los Angeles location is one of six storefronts around the world of streetwear giant Supreme.

Supreme is known in the streetwear community for releasing new collections almost every Thursday. Hordes of excited shoppers, mostly young men, wait for hours in line to purchase Supreme gear at retail prices.

Here’s why: Supreme merchandise, like that of many other contemporary streetwear brands, is worth significantly more in the resale market. For many customers, reselling this gear has become a business and a way of life.

One reseller, Joseph, who declined to give his full name for privacy reasons, says he got into the resale business because “my parents wouldn’t buy the high-end stuff, [so] I started flipping in high school to cover my costs” for streetwear purchases. By the time Joseph graduated from college, he had started reselling streetwear full time. Now he has his own reselling platform, called eluXive.

The resale industry has been on the rise. In addition to the original Internet arbitrage tool, eBay, apps like Poshmark and Depop have begun to fuse the worlds of resale and social media.

And the most prominent sector of the resale market today is streetwear — a form of athleisure fashion that produces T-shirts, sneakers, and other ready-to-wear goods often adorned with simple graphics and pop culture references.

Streetwear resellers, members of the larger streetwear community of sneakerheads or hypebeasts, are part of a multibillion-dollar market, an entire industry driven by the existence of a secondary market.

When Supreme collaborated recently with well-known luxury brand Louis Vuitton, the retail prices, resale prices and online hype were all significantly higher than usual. A red Supreme and Louis Vuitton backpack retailed for $3,900 but had a resale value of $9,073, according to StockX, a company specializing in analyzing products’ resale values.

The U.S. sneaker resale market alone is around $1.5 billion, and this number excludes private sales that happen on social media, according to StockX founder and CEO Josh Luber.

He says that despite continued growth, nothing will compare to the early 2010s when the market was growing at 30 percent to 40 percent per year.