Christianity (and other organized religions) are vestiges of a very effective way of packaging culture. Replace "God" with "the community" and things make lots of sense. It's not a terribly new observation that an individual's perception of reality is constructed by society. Why not simply call that process of construction God? Yeah, when it's stripped of all forms of communal relations and obligations as all things under capitalism are, you're left with a very dumb kernel of "imagine a really big wizard" but the fact that it's endured at all goes to show how deeply woven religion was into the lives of people before us. The difference between religion and superstition is the order: religion is about understanding the world as we experience it. A ghost dog telling you to sell the organs of children is not religion, it is, charitably, superstition.