I think there's a lot to what you're saying, Cris. Some of the same motivations and indoctrinations that we see in superstitions seem to be at work in religion as well: learned primarily from parents, social sharing, belief without evidence, etc.
Take knocking on wood, for instance. Probably very few people ever actually do this when they're alone. You "knock on wood," and say it, when others are present as a sort of social announcement and acknowledgment of your wishes or desires, but mostly to gain approval and acknowledgment of peers that observe the gesture.
I think much religious participation is like this. I'm sure their are plenty of those that will pray before eating even the smallest meals, say "amen" aloud, raise their hands on high, and other physical gestures of piety. But these are gestures of piety that are meant to demonstrate your piety to others more than they are to seek approval of the supernatural agent(s) involved.
I think many of these "experiences" that people go on about as their "proof" of their supernatural agents' existence are likewise public piety, designed more to get peer approval and acknowledgment. Public displays of piety are almost a contest among some believers: little fishes on their bumpers, the number of children being indoctrinated in their families represented by equal numbers of decals on the back windows of their SUVs, crucifix necklaces, carrying a bible to work and school (leaving it in open and obvious at all times), signing the cross, offering a "blessed day" at the end of phone calls, etc, etc.