Yep its quiet ridiculuos I have stopped accepting paypal on my site selling scripts it was a daily occurence, little shits either using hacked paypal or chargeing back after download
This is a clear case of fraud, this guy has paid most probably with a hacked paypal account. Now the person on the other side of the dispute is therefore a victim also. Its a no-win situation rly, wouldnt bother wasting your time with paypal, they simply dont care.