I think you just answered your own question.

Yep. While there's certainly a danger that unions can get too powerful and lead to scenarios such as the UK being basically brought to its knees by militant unions in the 1970s, going to the exact opposite extreme and banning unions entirely (or rendering them powerless) would be just as bad, if not worse.

Tagging for later response

I'm in a union. So far, they've only proven themselves capable of getting themselves paid. Our annual bonus was cut by over half. Nobody they've represented seems to have benefited any more than if they had defended themselves. They took credit for things that were already happening. Yet they say "If we didn't have a union, the company would just walk all over us" when it was already a fantastic place to work.

I didn't really say otherwise, my point was your analogy is awful.

When work conditions were poor, its obvious why unions had great value. But now we live in world where significant changes have been made via laws, many companies tend to be generous with benefits and the value of unions are no longer as apparent. There are examples of unions being exploitive or actually killing jobs.

But again, I'm more bothered by government employees in unions. Helps encourage waste of taxpayers money.

When did the workplace switch to being unionized labor?

I can only speak for the union in the company I work for.
I was in a unionless company before. Than a merge with another company happened and suddenly we had a union. One of the first things they did was unifying the work contracts. We got a 13th month payment every year before the union. With the new contracts the payment was higher, but we only got 12 payments. The overall sum didn't change.
However they also altered our business trip conditions. Before the union 100% were paid. After the union 100% were only paid, if specific conditions were met.
Don't want to go too deep into the details, but to make it short the business trip conditions are worse than before.
So in my case the union made things worse. Our union also used some dirty tactics at the supervisory board election.
I still think that unions did great things in the past and there are probably still jobs and countries which need them.
I also support the union if they call out a strike. (They have a point, if they say they can't get good results without support.) But I won't become a paying member. Our union just did too many stupid things, which I can't forgive them ...

It all depends on country and at the stage of their development and industry you are in TBH. Some federal laws in some countries offer great protection to employees so unions are not needed to challenge if you loose your job on unfair dismissal.

100 years ago unions made sense.

For blue collar workers it makes send to have unions who offer strong support as generally they all do the same roll and can be measured against similar rolls around the country/world.

White collar office workers not so much as everyone pretty much has an individual role so hard to argue if you getting a fair pay or not when every job is unique. When it comes to negotiate wage increases generally a employee collective group do that. It goes a little like this, company offer 2%, employees counter with 3% increase, they always land in the middle lol.

Some unions are a toothless tiger. Will convince you that you are within your right then they backdown when things get difficult and the employees suffer.

I'm going to tag this as well, yes Unions are important.

Unions are very important as they form a counterpart to the company's power.

OP asks the question of why not go to a lawyer but lawyers are expensive. In my country the losing party must pay the lawyer, so if you lose your argument, have fun paying a shitload of money for nothing.

Unions deal with issues that arise within a their own environment and tend to get better agreements than outsiders because they know who they deal with and they know the applied terms and conditions better.

Unions had a great impact on working policies over the years, and, for that, I am very grateful.

However, the current Unions, mainly the ones from the public sector, in my country (Portugal) really disgust me, and I am talking from an 'employee' standpoint.

Nowadays, our Unions have a place at the government, the current party could not have a majority at the elections, so they've kind of formed a joint party with the communist and the far left party (lucky us...) in order to attain majority. The problem is that the Unions control the Communist party, so, they are now able to have a say on important decisions.

The 'heads' of these unions live at the expense of the money coming from the associates. As anyone can imagine, the cash flow is not insignificant, so, in order to maintain it, they must keep the associates happy, and are now in a position to obligate the government to meet their demands.
This should be a good thing, at least on paper; however, some things should be noted. Our country entered a huge crisis in 2008 (as so many other countries), and we ended up needing aid from the IMF. The situation was indeed, severe. In addition, we have way too many people working for the public sector (and this is not just an opinion).
Before this joint party, we were on the path of recovery, with a lot of strict measures I admit, but we were getting there. For instances, there were some companies that were being semi-privatized, companies that were causing severe deficit for the public accounts. The deals were already signed, and even, for some contracts, the payments had already been made. When the new party started functions, the Unions were able to make the new government cancel all the contracts, only because the workers (the public workers) were against this semi-privatization.
Also, we are now having a lot of strikes, with demands that, in my opinion, are completely ridiculous. For instances, in the public transport sector we are having like two strikes a month, imagine the burden that is for people that relies on public transportation to go to work, fortunately, that’s not my case. And, it is important to notice that, the great majority of the demands come from people that earn way more than the minimum wage.
The government keeps on meeting the demands, at least on some degree, and guess who ends up paying for this….. New taxes are being created, and this is completely unsustainable. I fear that we end up needing external help once again.

Well, that is just my 2 cents, and I do not want to generalize my opinion to all Unions around the world, but, for the Portuguese case, I really think that the Unions are ruining the economy.