That's the logic of collective bargaining. The best move is to get benefits that go to everyone equally instead of putting everyone in the position to potentia

That's the logic of collective bargaining. The best move is to get benefits that go to everyone equally instead of putting everyone in the position to potentially earn more. So increase the size of pensions and health care benefits. Also politically when the two sides are non-antagonistic the biggest reward possible is the one that's put in the form of an unalterable agreement to be paid by a future party.