It was likely return fraud and is super common with PC components. The logic is, is that your average customer service rep doesn't know how to correctly identify parts that are being returned and doesn't give a shit about the return as long as the customer doesn't throw a fit. I would imagine this is still the case with Amazon since there is little human interaction.

I worked with a kid at CompUSA who did that with GPUs. He got arrested, or at least, escorted out of the store in handcuffs. Back then, and I don't know about now, most retail stores had an RMA cage where one or two people worked comparing part number and serials for expensive part returns. When your name is on the receipt and you work at the same store, you are gonna have a bad time.