Fundamentalists of every sect are, pretty much by definition, strongly committed to the literal truth of all of their scripture. But the garden variety “believer,” I suspect, may often be more accurately thought of as a “suspension-of-disbeliever.” (Somewhere in the back of my head is that CollegeHumor video about religion as a species of fanboyism.) When you think about the actual functions that religious narratives serve in people’s lives, literal truth or falsity is often rather beside the point, and yet suspension of disbelief is a necessary condition of immersion in the story.
On this view, Richard Dawkins is a little like that guy who keeps pointing out that all the ways superhero physics don’t really make sense. (Wouldn’t characters with “super strength” would really need super speed as well to do stuff like punching through concrete? Shouldn’t Cyclops be propelled backwards when he unleashes those concussive eye beams?”) It’s not annoying because we literally believed the stories, but because our enjoyment depends on our not attending too explicitly to their unreality. People can, on one level, be powerfully committed to the idea that Han Solo shot first, dammit—while on another being perfectly aware that, really, nobody shot anybody, and it’s actually just Harrison Ford and a dude in a green rubber suit with some laser effects added in post production.