We all know them already and they are very annoying to be honest.
GMs told me to report any goldsellers so they will ban them, but this doesn't work well, they are still around and more then ever.
I don't see what is gold good for in this game, because i get enough from minigames to can buy everything i need, but some peoples still buying it(otherwise goldsellers wouldn't exist).
So why don't you just sell golds in itemshop?
I'm quite sure it wouldn't make the game more Pay2Win.. since simply the gold itself is not good for much, unlike the AA and raid access(but this is a different story)