[GauntletWizard]

Agreed. I think exclusive supplier contracts are pretty dumb, too - At least without clauses for 'Price match or get out'. And the solution to the former should be (and I'll admit this is a stretch) to fix that problem, or better yet: simply to make your union's services so attractive and obviously a public good that the significant majority want to be sure it sticks around. Yes, the free rider problem is universal - Unions cause it as much as suffer from it (ever heard of unions suffering from deadweight because of seniority rules? No, nobody else ever has either :P)

[pseudalopex]

Whatever you or I think about exclusive supplier contracts, is there a single state that forbids them except for unions?

Seniority rules are something unions negotiate for. Contracting firms stick warm bodies on projects all the time. That's between the supplier and the customer, not imposed by the federal government.

I agree it would be better to fix that, but as you said, it's a stretch. Good luck getting Republicans or Democrats to go for it.