It's the culture here. When a community grows they build up some common interest. In this forum it's a common interest that account buy/sell is kind of a shady job here although there are no written rules. So according to the common interest DTs tag the account buyer/sellers. Hope it make sense.

PS: I have seen some of the bought account who are laterally became valuable asset for the forum. So it's not right all the time that account buyers will do shady jobs.