[mothered]

Right, but what if that person will report what happened to the police? Since he has the serial number and the proof of purchase, if they find that I'm using the product they will most likely blame it on me.

It's very unlikely to go that far.

SE'ers have been social engineering phones with the sealed box method, boxing, wrong Item received, DNA etc for decades without Issues. If you're that concerned, purchase and register your product using fake credentials.