Well technically buyers joining hands to boycott wouldn't be a cartel. And it wouldn't work because due the nature of drugs, you are not factoring the fiending/craving/addictions etc.The vendor cartels can sit on a high price. A group of buyers might attempt a boycott, but you'd better believe that someone in that group will give in and place an order (even at the price they're boycotting)for reasons that will trump their principled stance.. you know?