It’s MSCHF, stirring up controversy is kind of their gimmick - I assume they set aside money to deal with legal issues, especially given the premise of “anyone who bought a shirt from the company that sent us a C&F first wins”.
Indeed, the idea of their art is about consumerism and hype and they all "sell out" quickly as they are in limited numbers. All we can look for is people who did get a "drop" in the post or who actually paid money for something.
But I think its funnier if we think that they have not sold anything at any time!