This is really strange. Unions should be there to protect workers rights when they are abused from above, ie they give more strength to workers when necessary. In normal working conditions, unions should be invisible.
Case in point: my girlfriend's workplace has been recently purchased by a multinational. Everything fine and well, until they had to pay her. Her monthly salary was cut by about €400 because they refuse to pay past overtime work (which is perfectly legal here, was required by the old employer and was 100% documented). She then gathered with her colleagues and they decided to sign up with an union to put some pressure to the new employer. It happened last week so I have no more news.
Anyway, that's what unions are for, at least over here; they shouldn't be used to move furniture or things like that.
The US is setup differently. The local/state labor departments usually handle pay issues, and almost always force the company to pay/backpay employees. I've dealt with them on occasion, and they do an amazing job in the US. When dealing with the State labor board, the company needs to prove their innocence (which is right because they are expected to have better record keeping).
Unions, unlike in Europe, function to protect hours for hourly workers, carve out job functions for union-only work, set standardized salaries, and prevent dismissals. Historically they did a lot more with worker safety, but that's been taken over by the federal gov't (OSHA).
It's just not comparable to the EU. The words almost mean entirely different things - and that's why talking about it in this forum can be very confusing, and often needlessly antagonistic - because the words just don't mean the same thing.
Case in point: my girlfriend's workplace has been recently purchased by a multinational. Everything fine and well, until they had to pay her. Her monthly salary was cut by about €400 because they refuse to pay past overtime work (which is perfectly legal here, was required by the old employer and was 100% documented). She then gathered with her colleagues and they decided to sign up with an union to put some pressure to the new employer. It happened last week so I have no more news. Anyway, that's what unions are for, at least over here; they shouldn't be used to move furniture or things like that.