> There's a god in my national anthem,
Assuming UK here, in which case you don't have to sing it very often or every that but yes Head of State is Head of Church so those are still overlapping.
> there were prayers to a god in my school assemblies,
Does that mean you went to a CoE school? Many of them are but it does say it on the sign by the door.
> the cub scout promise I had to say every week was to a god,
Again, a Christian organisation to bring up young men with Christian values, you are going to end up mentioning god in there somewhere.
> the oath my MP swore was to a god,
Well I think we have the Head of State = Head or Church history thing to thank there again too. Does that mean that it has to be the Christian god or does any deity fit? Does this mean there are no non-Christian MPs?
> my doctors swore that they would not 'play god'.
I am not sure the hippopotinus oath is mandatory in the UK but again that is a non-specific deity; though I grant you an Atheist taking such an oath is worthless as there is no god so there is no action they can take which will be considered playing god.
Many cases people who don't want to religion could avoid it, yes it happens outside of temples but most of the time it is not a trick and you can avoid it if you check up on things first.