I had one bad experience with one union. I was part of a team, hired by a large company, to track down, identify, document, and render operable, repairable or scrap every item in their very large network of routers, switches, servers, computers, and printers. It was a month long effort.
The union assigned me a "minder" who followed me around everywhere I went. In order to get data plate data I had to move the equipment so I could see the back of the device or the bottom of the device. Every time I started to move a piece of equipment I was warned to stop by my union minder who filled out a work slip so a union member could be assigned to move the equipment. Because they didn't just assign a union toadie to help me I had to wait for the work slip to be routed, approved, a worker assigned, who eventually showed up, and then I had to sign off that the union toadie did the work identified on the work slip.
This task took between 3 and 4 times longer than it would have if I had simply moved the items myself.
I hate union. I hate union thugs. God, I hate Democrats.