>But US unions seem to exist nearly exclusively to protect people who don’t want to work.
They don't exist for that reason, but their inevitable ground state is that.
The fundamental and intractable problem with any form of socialization is that it naturally attracts free riders. The idea doesn't have a balanced equilibrium, so it's either logistically/bureaucratically heavy or always being pulled towards collapse.
Everyone who starts these systems has pure intentions, and the initial members tend to be dedicated too. But over time it will either naturally decay, or turn into the thing it was trying to fight.
A healthy organisation can reflect on this tendency and purge some free riders to preserve itself. The fact that it doesn't, to me personally, just means it's not under external pressure.
This doesn’t seem to be a universal rule at all, but smells more of a boogeyman promulgated within US society.
The nordics are anywhere from 50% - 90% of all labor unionized and they absolutely destroy the US on every standard of living metric.
It seems to me a case that echoes “better to let 99 guilty men go free than to execute an innocent man”. Of course, in this case, the ratios are actually reversed. Should we execute 99 innocent men to make sure that 1 guilty guy gets punished?
There will be some free riders, just like there will be some welfare queens, just like there will be some voter fraud.
That said, these cases represent a vanishingly small minority of the whole, and the cure is far worse than the disease.