u-Bob

Unions and their influence are different in different parts of the world, but in general: there's nothing wrong with a union per se.

If workers want to organize themselves and have someone represent them in negotiations etc with their employer or potential employer, there's nothing wrong with that. People are free to associate themselves with whoever they want. Employers are also free to hire whoever they want, so in a free world, employers would also be free to refuse to hire people who are represented by certain organizations like a union for example. Freedom works both ways.

The problem with unions and the way they operate in most countries these days is that they have become a part of the state. In this part of the EU for example, every couple of years a small number of people who represent a couple of 'employers organizations' and the unions get together and discuss how wages will go up or down etc. These talks influence not only the people who are a member of those unions but also the people who aren't.

Years ago, before I became (full time) self employed, my boss asked me if I wanted to work on a holiday. They needed a small group of people to work that day and offered 3 times the normal pay. I agreed to work that day, as did a lot of other people. But in the end we weren't allowed to work that day because some union (that I wasn't even a member of) refused to ok this deal. So my boss voluntarily agreed to the deal. I, as an employee, agreed. But because of some union (and the powers it has) we weren't allowed to complete "our voluntary transaction".