I don't know about the legality of this, and so I won't say much about that. What I will say is that, when the campaign was first announced, the same utterly mediocre spokesman was on Sunrise, where he ummed and ahhed around a question which plenty of people would think - "do we really need this in New Zealand? Religion's not that big here anyway." The fact that this campaign has been blocked demonstrates that, yes, we do need this in New Zealand. For the majority of New Zealanders, religion is an irrelevance; but there are enough for whom it isn't; people who are so pious and dogmatic about religion that they somehow get offended by a simple, plain statement that there are people who disagree with them. It really shouldn't be a surprise - look at Family First, remember Destiny Church's "Enough is Enough" march (in fact, just remember the Destiny Church, and you'll realise that, yes, the forces of fundamentalism are there, and they taking a stand against equality and freedom). Not to mention, down at Union Lawn at the Uni here, where about a fifth of the stands are for various campus Christian groups (I have already got given a Gideon's Bible!)
No, religion in New Zealand isn't quite as all-pervading as in America, but it is there, the full spectrum from the largely inoffensive Anglicans (who are helping sell my old textbooks this week), all the way through to the sexism and homophobia of the Destiny Church - and every level in between. There are people trapped in the cycle of the fundamentalist religions, and they barely realise that there are people who identify as atheists. Those people will sit up and notice when they see a sign saying "There's probably no God." They already have, before the signs have even gone up! That's why they complained, and the fact that they complained is evidence that, yes, the target audience is out there, somewhere.
I just finished reading a book, Infidel by Ayaan Hirsi Ali. It's her memoir, of growing up in fundamentalist Islam in Somalia and breaking free, to become a controversial Dutch politician. One moment in the book really stood out - when she a teenager, talking to a boy she quite liked. She finds out that, not only was he not a Muslim, but he didn't believe in anything at all - he was an atheist. This is shocking, and she knows straight away that it is over with him - but what really stands out is that she didn't know there was such a thing. Eventually, she becomes one herself, because she asks questions. There is great ignorance among the religious about what exists outside of religion. People need to have the seed planted, not so much to turn them into atheists, nice though that would be, but just so that they are informed, so that they know such a thing exists. I have nothing against the fact that some people do, and will, make the choice to believe in weird religious ideas - that is what should happen. What offends me is that many people don't know it's a choice - they are slaves to their beliefs.