I occasionally have problems with ALP (Australian Labour Party) policies, but feel it is better to fight them as a member, than as an outsider. For instance, our former PM Julia Gillard is against gay marriage, as is my local federal MP. I have told him I disagree with his stance: he took it in good spirit, but was of the belief I was in a minority in our federal seat, which has a lot of country folk in it.
No matter - I had my say, which means more as a party member.
Also, as a member I get more information about Labour and union matters, and have various ways of putting my own fillings in. And this week I voted for party leader, something new: we never had free plebiscites for the leadership before.
Better in than out imho