"I think this culture only started to really pick up over the past three or four years. One of the main reasons is the growing popularity of sports, especially basketball. Also, more and more online influencers have started wearing them as a fashion statement," he says.

Ma, who formerly spearheaded the National Basketball Association's promotion efforts in China, concurred, saying that the NBA "has done much to cultivate this culture".

The NBA's influence is evidenced by how the Air Jordan series of sneakers has been one of the most popular in the market. Another popular line of shoes is the Adidas Yeezy, which was designed by US musician Kanye West. Launched in 2015, the variants of the sneaker are among the most commonly found on resale sites.

According to Xu, who was formerly a public relations manager for Chinese athletic brand Li-Ning, the sneaker craze has been a boon for local companies as well.