Selling on Amazon requires a registered trademark. If you're a random factory in Shenzhen you don't care about branding, you just want to be able to sell your stuff on Amazon, so you just put together random letters in the hope that your registration won't conflict with anything else. You don't want to have to deal with back-and-forth with USPTO, you don't care about having a meaningful, memorable, or interesting name, you just want an Amazon listing.
Coincidentally the majority of USPTO trademark submissions are literally just random strings of letters now for this reason.