In creating a world for fiction it is important to not work yourself into a corner. In some stories the only thing holding the entire plot together is a single idea or running gag (I see what you did there Walden--not that it was bad for its age group). This kind of lack luster world building can cause the whole story to seem flat whereas well crafted worlds can create beautiful settings to hang your characters on. Thus when deciding how people and nations worship (or don't) it is important to give the issue some thought.
