I think that's fair enough, but it's not like workers in the USA have a lot of protections or are getting fairly compensated for their work. So unions, whether compulsory or not, still benefit them in one way or another.
How did they end up not having enough cash on hand to cover minor emergencies, then? How are they going bankrupt over healthcare costs - even when insured through their job - while having to worry about not being able to take a day off?
This isn't just uniformly true, though. As a worker you may be better off without the union you're a part of- it depends as much on the union as the company.