> A union does whatever its members want the union to do.

Just like a democracy does whatever its voters want it to do?..

Different people want different things.

> I'd argue that an environment where pay negotiation is a case of every person for themselves isn't actually good for anyone but if the majority of members disagree with me then the union won't get involved in pay.

Well, I feel for the minority that doesn't want the union to get involved in their affairs.