As I understand most states already prevent unions from collecting the kind of payments that were discussed here.
If you can benefit from a union's negotiations without contributing money to them, why would anybody join?
I dont understand it but most states already have right to work laws so we see the answer. There are still unions, just fewer of them.
One quirk you might find interesting. Our federal labor law on unions dates to prior to WWII, while Germany's is younger than WWII, as the old system there had to be de-Nazified. In Germany, an employer has to make sure that each of their employees belongs to a union, even organizing a union themselves if one doesn't exist already. They have to set aside company time, as part of this union activity, where workers can discuss work issues without managment. These meetings have turned out to sometimes produce good ideas that help everyone in the company do better. German companies like BMW first started moving some work over here, they set up these unions and these meetings at first - but our 80 year old federal labor law, as interpreted by SCOTUS, bans this. BMW was stopped. In the US a labor union can only be set up and run by workers.

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