All it takes is a GM to visit the usual nodes and spectate. The bots are pretty easy to tell just by observing. Once they see them they can begin the investigation.
I'm pretty sure they know the procedure which makes me believe they either don't want to take any action because those bots also pay for their sub or they simply don't have the technical mean to prove that those players are botting.
I've made many reports in the past and nothing happened.
As for the Gold Sellers in town. I'm pretty sure they are solely focused on those as they do indeed ban them.