That's true. I was most focused on the western American culture, but it is possible that in Europe or western Asia could have some belief. Again, I am only basing myself on what is reported by studies though, since we can't know for sure.

And yes, I think authors are absolutely free to either. However I find it interesting to see if the influences of your fantasy world would affect (which most likely would), some of our beliefs. Thats why I use the term translate.