[jschwartzi]

By arguing from the standpoint of raising or lowering prices you're being very reductive. Doctors form trade associations too, and yes the prices for a certified doctor are much higher, but the quality of care is also standardized and usually higher to match. OP wasn't making the point that industry associations don't raise prices. OP was pointing out that most industry associations are formed to try to make things better. And that might result in increased prices, but that's a side-effect and not the goal.