I think we cant stop that, like it or not but they can make some trade volume on this market so somehow they are important thing to make this market grow. Im not fans of the pump & dump system, for me they just like destroy some trading system by manipulating sell & buy order. Because of that the reputation of cryptocurrency can be bad.
They are doing pump and dump with their own funds and we can't accuse them all about that. It looks like this will be gonna to run anytime. This is just like another ponzi organization which created a scheme to earn more and more money. this is blockchain and any funds will be covered by algorithm.