Atheism is unstoppable.

[Belacqua]

Please demonstrate that this is true.

It's why we have fiction and non-fiction labels, to designate a fictional story full of tales from a non-fictional memoire or history.

Do you mean it's illogical for someone to want a tale to have a basis in reality?

Indeed.

The Tale of Genji is fiction. It tells us in wonderful and inexhaustible detail about how real people in Heian Kyo thought about themselves, other people, and the natural world. It gives the attentive reader a matchless experience of familiarity in the midst of a wildly unfamiliar society. It is a wonderfully worthwhile way to see how different human lives can be from our own narrow experiences. And this novel is just one example.

So I reject tout court what you say about tales. 

Religious tales may have this purpose, or different ones.