A lot of premium resource authors are adding people to the buyer list in order to get good reviews out of them I have 2 ideas how to handle this 1. Simply disable buyers from the buyer list from reviewing the content. 2. If the buyer got the product for free ( aka added to the buyer list ), create a little warning in his review, saying "Received product for free". Now I know in some weird cases real buyers are added to the buyer list, that is extremely uncommon, and even then, This suggestion doesn't hurt them in any way shape or form.