Tequila Bar Submits Paperwork to Become a Church in Attempt to Stay Open
https://www.foodandwine.com/news/tequila-bar-church-nottingham-england

This is comic, but it points to a really important issue. Who gets to decide what is and isn't a church and what rights of assembly can be infringed what ones can't?

At least for me, none of the answers are obvious.... except that a bar is not a church or a union hall or a political party headquarters and at least in the US, it would not be protected speech or assembly AFAIK.

Its easy enough to set up a church though.

A list of the Christian ones is mind blowing.
https://en.wikipedia.org/wiki/List_of_Christian_denominations

I remember a One Eyed Cow in Vietnam. So why not 400 rabbits?

The Church of The Flying Spaghetti Monster (aka Pastafarianism) has gained some legal recognition in some US states.
https://en.wikipedia.org/wiki/Flying_Spaghetti_Monster

There is also Jediism derived from Star Wars which has some sort of traction in the UK.
https://en.wikipedia.org/wiki/Jediism

Neither would be much help in keeping a pub open during a pandemic.