Unions ARE a necessary evil.
They are the only ones you can turn to after you have made many attempts to sit down and work things out with your company. The name of the game is to get power and lawyers and skilled negotiators behind you so then, the company HAS TO listen and HAS TO commit to written agreements.
From that point on, it's all about politics and money, and nobody comes out clean, but some of us get protected.
There will never be a perfect balance, it's either the Local holding the cards, or the employer doing whatever they see fit if there's no employee organization. For all it's shortcomings, I'll still take the union protection over leaving my fate in the hands of my employers, if I had to choose one or the other. Paying the mortgage and keeping my family fed are of paramount importance. I've experienced what it's like when the employer does whatever they want. I've never had any performance or disciplinary issues, but I've seen many that have been screwed over.
Unions, in theory, are a good thing. The Local needs to be smooth about things, agree to givebacks if truly needed, and strive to be productive for the premuim that the employer's paying. The union may continue to drain their employer's resources, then say WTF when massive layoffs are implemented, or when their jobs relocate to a more cost friendly locale.
Edit: I like the way things are here - we have progressive discipline, we can be denied a merit increase if we underperform, I've seen a few individuals get fired or "resign" since I've been here. We also have representation by the Local for any grievances, all of our SOP's and their penalties are clearly stated, we have people constsntly going to bat for us to preserve our compensation, prevent layoffs, keep safe staffing levels, to protect our retirement system, which they made sure the county kept funding. They saved my job back in 2009, so I konw I made the right choice to join. It's voluntary, being a right to work state. Our political influence gets the job done. Right to work states aren't too bad if you have a large enough Local with enough lobbying power and such.