They need to do double blind testing - there's a good chance the experts would think these crappy speakers sound just fine if they didn't know what they were.
I'm thinking the opposite. I mean, laying down 500 quid for a very amateurishly packaged speakers off the back of white van? We're not talking 5 for some bad smack. I think the pricier the scam the less likely it is to be illegal, especially for audio equipment.