I don't know, i'm guessing it has something to do with ww2, entire generations of men coming back and not talking about it. Mind you, the english can atleast debate each other (not so much atm due to pc culture, still, moreso than us). It may also have to do with the fact that many of our ancestors were poor/working class , but unlike in the uk we were able to achieve social mobility and there is an unspoken act that goes along with that, social etiquette to not stand out/be caught out , be acceptable don't rock the boat (tall poppy syndrome). i think many of us learnt from our parents who learnt from grandparents era and so on.

We also are quite naive about the world, many do not travel globally or spend authentic time with folk from very different cultures (beyond the pacific) and although we want to do the right thing, we can be a bit basic or idealistic in our grasp of what that is.

Might be talking out me arse but whatever it is i think it's also the cause of why so many kiwis (and foreigners whom try to interact with us beyond our kiwi pleasantries) find it so hard to make friends (not just associates) outside of school.

I kind of think nz developed so fast and socially we were not ready to loose the sense of community. I also notice alot of cultural differences between North island and south island pakeha folk.