I've sold an account last year. It had big potential rank.
I don't know how many hands did it change, but now I've seen it around very often. It's in a signature campaign, it's already Hero and it seems to have pretty good quality posts. So it's not always about scams...Some just make a good business from it.
what you are saying is true, it is upto the users who buy and utilize it , we cannot judge everyone to be scammers , their are users who buy high rank account and utilize it properly.