Ever wonder what is that? I can't believe Valve or the developer look at it as a trivial matter because I still can see "boosting service" advertisement by VikingDota in Youtube.com. When Valve was fighting with Blizzard to become the developer, I thought Valve can improve Dota 2 into a better game with the better community standard than other MOBA games such as League of Legends. Too sad, what I was expecting actually not right because Dota 2 community is becoming worse and worse from day to day. All these boosting service that increasing the mmr of an account which does not belongs to the real owner really can spoil and bring down the community standard of Dota 2. But this Valve like never care or no action been taken on those mmr boosting service and account selling sites.