Nikki Finke puts it best as to the wherefores and hows of the evangelical-produced, directed, and scripted Fireproof coming out of nowhere doing big business on less than a thousand screens.

Why can't other interest groups can't band together and make a film explode like this? They're not nearly as organized or fanatical. As much as evangelical Christians want to call out atheists, deists, and agnostics as being organized armies of the devil, they are not as regimented as the Soldiers of Christ-types are. I bet Religulous won't do as well as this one proportional to per-screen average for that reason.