upscale audio is this legal?

Maybe I'm wrong but wanted to get the communities thoughts. A good friend of mine bought a Cary amp from upscale audio it was supposed to be a v12 i. That was a year and a half ago recently he was going to sell it and was looking at the receipt from them and the serial numbers dont match at all!! totally different amp not even a i series. well he called them and they told him there was nothing they would do. I have never checked the serial number on anything I have bought but will from now on.My friend assumed he was getting what he paid for but did not! You would think they knew somewhere along the line they sold him the wrong amp . anyway whats your thoughts.