How would the shipper know who would get the item?
Somewhere you have to be honest with your seller.
He needs your name and address to ship.
An experienced seller knows not to accept prepaid shipping labels, because they are part of a very common scam, where the buyer rips off his employer's shipping account to send the label. When the company's bookkeeper notices the seller gets hit with Violations.
However, as a person with several names making up my legal name, I do use different parts for different accounts. As is John Jacob Jingleheimer Smith might be John Smith in daily life and Jingleheimer Smith as an eBay seller and JJJ Smith as an eBay buyer.