I have found these gangs of Moonkins on several servers. One favoured place seem to be Koramar in Zuldazar where there is a good cloth farming place.
Two or three gangs of Moonkins often seem to be active at once. After a while I’ve seen other players log in sitting on Acution house mounts in the middle of the farming groups so there is no need for moving.
Obviously there is a lot of profit in doing this - the question is how this will affect the economy of the game.
In any case it’s not any fun to do any kind of farming when you bump in to multiboxers - I have almost stopped doing professions, and I refuse to buy maths from the Auction house and feed these players.
Maybe that’s the solution to the problem - stop buying their materials at the auction house. No income no farmers.