You can draw a parallel with the Napster affair and it's later distributed incarnation, Bittorrent trackers. Exchanges are vulnerable but they are many and easy to start.
Perish the thought that someone might get any financial freedom or privacy. No, we can't allow for that since the criminal might use it. Come to think of it, car and road builders make huge profits when criminals are allowed to purchase their products. They fully know that criminals use the motorways each and every day and move with impunity, and yet they do nothing about it ! I believe the solution to this travesty is to register each and every person that uses a car, which should submit ahead of time a detailed plan of his daily itinerary. Every driver should be fitted with an explosive collar that would automatically go off should he steer off route.