Just as a pendulum ultimately comes to rest in the middle, you'd think that eventually labor/management relations would realize a stable, middling course would be better for both parties in the long run.
But all to often someone comes along a gives the pendulum a big shove. And I agree with Toad, greed is the prime motivator.
I think Lazs' idea has some merit, except that to expect a lawyer to negotiate in good faith on behalf of the employees, the lawyer must be paid by the employees - otherwise its a case of hiring a fix to guard the hen house.