Amid the towers of bulk toilet paper and cereal,  Costco members are increasingly flocking to the wholesale retailer for a surprising reason: fashion. 

While  Costco might not seem like the obvious destination for stylish clothing, the warehouse store is raking in more than $7 billion in apparel and footwear sales, with revenues in that category growing 9% a year for the past four years, according to  The Washington Post. Though most of  Costco's 800 stores are large warehouses across the US lacking offerings like fitting rooms, shoppers are increasingly making room in their carts for heavily discounted North Face jackets, Jessica Simpson jeans, and Calvin Klein blouses. 

" Costco has quietly become an apparel destination," Simeon Siegel, a retail analyst for Instinet, told The Post. "It is clearly resonating with shoppers and winning over brands at the expense of department stores." 

Perhaps most impressively,  Costco's apparel sales - which also include products from its  namesake Kirkland collection- are outpacing some traditional retailers like Old Navy, Neiman Marcus, and Ralph Lauren.  Costco's success in the fashion sector is partly thanks to its captive audience of 85 million members who pay an annual fee of $60 and up for access to discounted bulk goods. 

Add the fact that fashion companies are seeking out viable ways to unload excess inventory - and a willingness to do so even at a seemingly unglamorous venue like Costco, thanks to its largely affluent client base - and you've got a recipe for success.