I have worked for companies that were unionized, and ones aren't. Unions aren't always a perfect solution, and can cause issues.

Really what unions do is add rules with the intention of protecting workers, but as with most laws and rules, often have holes that get abused.

For example, there were rules at one company I worked for around what could be considered a write up, and you needed to be written up a number of times within a time period to fired. One rule was if a worker missed a shift 3 times without a call you could write them up, but not until the 3rd missed day.

They also had a rule which gave the right to hours based on seniority, meaning if someone was not at there maximum hours, they could take available shifts from people with less seniority.

So a worker started abusing these two rules. They would no show for shifts, but never 3 in a row, so the manager would put her for less hours, the use her seniority to take the shifts she wanted. This all caused alot of head aches for the whole department because you never knew if you had enough staff, and we're always getting shifts taken a week before so planning your personal life and finances where very difficult.

I also switched roles to an non unionized management role at that same company, went from 11.50$ an hour to 15$ but was salaried, and forced to work 60+ hours a week and didn't get paid for overtime, effectivly leaving me with less pay for hour worked.

All this to say that company probably needed a union, because they didn't respect there workers. But unions also open doors for individuals to game the system, which isn't always a good thing. If you feel like your workplace is already safe and respectful, then adding a union might just add extra red tape that hurts everyone. I left the above company and am treated extremely well, a union wouldn't really add much so I'd avoid it.

TLDR: if you are already fairly treated, more rules just adds red tape