"we pay a union to halp, advise and support us in our choices."
A trade union is not just a professional club that just sends you a magazine every so often. Did you not know that when you joined?
The right to form and join a trade union for the protection of workers' interests is enshrined in the Universal Declaration of Human Rights it's considered to be that important. A trade union is a collective of workers who have banded together to ensure that their employers do not impose unreasonable conditions upon them. They bargain as a collective, and they act as a collective, because their strength is in their numbers. The employer might be able to ignore the complaints of a couple of people, but when a trade union speaks for all its members, that is not so easy to ignore, because the trade union can ask all its members to act.
For example, in the first school I worked in, there as a big problem with behaviour. It was getting worse, and one teacher in particular had been assaulted by the same student twice and didn't feel safe to teach him any more. The head proposed various measures, none of which included this student being permanently removed from the teacher's class, so the teacher got the union involved. The union called upon all its members in the school to refuse to teach the student. This caused chaos, and eventually alternative provision was found for the student.
When you say you want the support of a union, that is why they are in a position to be able to support you. That is why an employer is prepared to listen to a union. Not because they want to, and not because you've paid subs, but because of what a union is.
If you don't act when your union calls upon you to act, then you are weakening the union's position.
If you don't want to act when a union calls upon you to act, then perhaps a union is not something you should belong to.