But isn't this also true of many other countries one might find more to one's liking?

I tend to think that something akin to " The Assemblage of Atheists and Agnostics" would sound better that calling at a 'church,' since, to most Atheists, the word "church' simply reeks of Organised Beliefs and Rituals, etc.

creating atheist churches are a way to fight against non secular laws and actions.
Many "rights" and privileges only trigger if you have a religion, that means that you are choose a religion and have those special rights, BUT if you don't have a religion you can't claim them. This way by creating those mock religions it shows that:

1. Beliefs are arbitrary and by claiming religion freedom you can get away with too many things, so this must me limited.
2. In case of 1 is not observed, you can at least use this special rights and privileges to at least have some space to talk abut rationalism ans science.

Many schools or cultural programs have religion thematic events" where religions have a space to talk.
Some of them includes secularists and/or atheists association, giving non-religion the same rights. BUT some of these events deny secularist organization because they are not religion. So the obvious way is to create a mock religion.

And taxes, of course.

Vegans do the same for food rights. A Jewish or muslim can ask special food, but vegans can't. So they create a church of veganism to claim the right to not eat meat.

@Pedrohbds I don’t agree, but I’m sure others may.

I just saw it yesterday. A little uneven, but hilarious at times, and thought provoking.