Probably not a scumbag seller but rather another one of those hoarders/scalpers/resellers. If they do anything blatantly suspicious or against the rules then there is quite a high chance they would be banned and removed from the website if they use some sort of fraudulent pattern of behavior, pretty easy to spot. Of course you are supposed to report them if anything like that happens, but reselling stuff- no chance, no one has ever forbidden that and that would be extremely stupid