Because...Detroit.
The greatest problem for unions is their yoke at the neck with Bolshecrats. Until, unions realize they have a better future working with companies to build products more efficiently, instead of what they can get out of a product, they will never achieve what they want. Their relations with the Bolshies, who will only add to their woes with the force of law, will eventually bite them in the ass. That relation can only result in wage and price controls.