Churches refusing facilities for Civil Unions

An issue that I've been mulling over is whether churches (or, for that matter, taxi drivers) are entitled under the law to refuse to provide their services/facilities for civil unions. First, it's clear that celebrants are not required to perform civil unions if they don't want to (see s13 of the Civil Union Act 2004):

Licence authorises but does not oblige— A licence authorises, but does not oblige, a civil union celebrant or an exempt body to solemnise the civil union to which the licence relates.

But, secondly, I think the question of refusing services or facilities is not as straight-forward. My quick instinctive analysis (without any significant research) is as follows: 1. The prohibitions in sections 42 and 44 are both engaged. That is, discrimination on the prohibited grounds (sexual orientation, marital status, and family status) is prohibited. 2. Both ss42 and 44 have internal qualifiers which must be engaged: facilities "available to members of the public" or person who supplies facilities "to the public or to any section of the public". In each case, it must be established that, factually, the provider is providing facilities to the public (ie, if, across the board, they do not offer their facilities to anyone then the Human Rights Act protections will not apply). 3. Both ss42 & 44 are subject to various specific exceptions (limited to discrimination based on specific grounds of discrimination). For example, s46 allows discrimination arising from "the maintenance or provision of separate facilities or services for each sex on the ground of public decency or public safety". None of the exceptions seem to relevant. Notably, a couple of the other specific exceptions which could be relevant in relation to other spheres of activity are not replicated for the purposes of ss42 & 44, eg: - the "religious purposes" exception in relation to employment (s28) - the "marital status" exception in relation to employment (s32). 4. A more general justification – such as the usual balancing process that would apply under section 5 of the Bill of Rights – is not available in the first instance. However, the Human Rights Tribunal has the power to declare something lawful if it constitutes a "genuine justification" (but subject to certain, quite reactive, procedural requirements). My quick search only shows one reported case in which this was done: Avis Rent a Car v Proceedings Commissioner (1998) 5 HRNZ 501 (practice of refusing to rent cars to under 21 year olds was genuinely justified by refusal to rent cars to 21-24 year olds was not). The mediation between religious freedom and freedom from discrimination under this provision may allow the discrimination – although, off the top of my head, when considering similar contests (sexual orientation and schools etc), the Canadian courts have generally come down in favour of vindicating the freedom from discrimination/equal treatment. I’ve included the relevant provisions from the Human Rights Act in the comments field.