Here’s a bit of fashion news that definitely wasn’t on our 2023 bingo card: Costco-branded clothing is trending on TikTok. We’re not referring to the usual crazy deals for designers like DKNY, Vince Camuto, Steve Madden and Banana Republic. We’re talking about sweatshirts, joggers and slides sporting huge logos for Costco and its private-label brand, Kirkland Signature. Is this some kind of reaction to inflation? A backlash against designers and fast fashion? Is it all being worn ironically? Many of these styles are being released in small quantities in stores and online, which turns them into instant collectibles. Intentional or not, it’s a strategy that appeals to millennial and Gen Z shoppers who are accustomed to snatching up limited-edition “drops” from their favorite clothing brands. When we stopped by the Costco warehouse in Gaithersburg this week, we couldn’t find any of the popular logo-wear in stock. But if you really want it, there’s plenty available on eBay — at a steep markup, of course.