[Apocryphon]

Here's some issues that a collective advocacy organization could help with:

https://news.ycombinator.com/item?id=15596221

Also:

"Even if you don't believe in unions, unions are necessary to force the hand of government. Bismarck instituted a welfare state in Germany to undercut the popularity of socialism and the left. You need unions to get to a stronger safety net, even if the powers-that-be are establishing it in opposition to them."

[Fins]

As a single data point, I worked at a union shop once. It wasn't very good.