Earlier quoted context omitted.
I've often heard that the biggest problem with unions isn't higher salary and benefit demands but inflexibility. Unions often insist on things like work rules (who gets to do what) and are resistant to automation or other forms of efficiency improvement. They basically end up mandating that things never change, eventually killing the host. From what I know of union work rules I can't even imaging trying to run any fo…
Union rules change all the time. Management just isn't usually willing to offer sufficient incentive during negotiations, since that would eat in to their profits.
You want everything as cheap as possible, which means you want everyone else to not belong to a union. But you want to be paid as much as possible, so you want to belong to a union. Your economic self-interest would be maximized if you were the only unionized person on Earth... but of course that's impossible.
It's not just "corporate greed." I mean that definitely exists and many executives are over-compensated, but compared to other costs like capital, labor, and taxes, that's usually just not that big of a cost center for a large company. That's part of how they get away with it. If CXOs were a significant cost center the shareholders would be less tolerant of those fat compensation packages.