I agree that unions have done a lot; the point is that the evidence shows it to be a double edged sword. Following the link I posted, it explains how one effect of current collective bargaining agreements enables owners of sports teams to cap the percentage of the overall revenue going to players. For example, collective bargaining has given us free agency in baseball, which has been great; it's also given us a system in which players don't hit free agency until they've been playing for 5 or 6 years, at which point they're usually in their late 20's or early 30's, and have missed prime earning years on the free market (having to settle for whatever comes out of the arbitration process).

Some of the increase in pay is due to the union, and they should be applauded for that, but part of the increase in pay in all these leagues also is due in part to the increase in revenues from media deals