I had the misfortune to try and negotiate with some unions in previously mentioned job - it was about a strike.
The demands from the union were all about pay, as per. However, not to be too outing, we were tasked with finding out exactly what the issues really were in the organisation on behalf of the organisation, and pay was literally the bottom of the list. It was a clear case of horrendous leadership, and so we were able to get this through to them - and amazingly the unions agreed to call off the strike on the condition that leadership made agreed changes etc. Anyway, we thought we had achieved the impossible, the strike was called off. WoW!
Anyway, the union went back on their word and went on strike anyway. And reverted back to their original mantra - pay, pay, pay. It was very obvious they didn't actually want to work with the leadership to improve things after all (hence also for staff) and they wanted an adversial relationship - that is the only way they exist. Pay would not have solved the issue, and in the end it felt like that was deliberate. Impossible demands that won't solve the probelms so on and on it goes, all the while they receive their hefty salaries. It's rotten.
Imagine all workers issues were solved? They'd be out of work.