Religion means lack of religion

We've got some new legislation to make the latest guidance on how many people can hang out together absolutely clear as mud. One of the things you're allowed to have up to 30 people in one place for is religious gatherings and their non-religious equivalents in the case of weddings and funerals and so on. It's written in a way that implies that weddings are religious ('weddings and other religious life-cycle events'; 'other' meaning 'as well as the one just mentioned'), which of course they may not be at all, or they may be a fundamentally religious thing - that's dependent on your religion and beliefs. So then they qualify this with the following wording (it's the same wording as in the EHRC, I just hadn't read it before as I don't make a habit of reading legislation): 

(1) Religion means any religion and a reference to religion includes a reference to a lack of religion. (2) Belief means any religious or philosophical belief and a reference to belief includes a reference to a lack of belief.

Pragmatically, you wouldn't normally include 'lack of X' in the meaning of X. More likely, we add a bit of meaning along the lines of 'if relevant' - the old joke about the boy who was late to school because there was a sign saying 'dogs must be carried' and it took him ages to find one relies on this, as the boy failed to infer the usual additional meaning 'if one is present'. 

When we use nouns (like 'religion') usually, we don't include the lack of that noun in their meaning. When I say that the purpose of university is to provide an education, I'm not including 'lack of education'. If I say that the role of politicians is governance, I don't normally include 'lack of governance' in that (insert your own wry comments here). 

You can sort of fiddle with this to fit in with that interpretation, if you say that 'religious' applies only where relevant, like the 'dogs must be carried' sign. But in fact it's more a reflection of the fact that rather than the default being religion and not having religion is a lack of the thing (X or not-X), we now recognise that lack of religion is an ideological stance as much as having religion. The fact that there are many religions probably makes this meaning easier to arrive at, because rather than X or not-X, we have options A, B, C, and D, where one of them is a lack of any religious belief, or 'none of the above'.