It’s one of the standard stories – a couple isn’t really religious, but they have a kid and think their children needs religion so they start going to church. What are they looking for? An identity; a set of moral guidelines for their children. Less Wrong needs to move into this market space.

The problem with this is that rationality is not warm, fuzzy, or comforting. In the example you give, parents are seeking religion so that they don't have to tell their children things like this. Quite frankly, some people just don't want to face the truth if that truth is ugly enough. This is why it's really hard to teach people rationality, because it requires significantly more effort and independent thought than becoming a member of a religious community. While I would certainly like to see more parents teaching rationality to their kids, the unfortunate reality is that a lot of parents would rather have their children be exposed to spiritual untruths rather than unsettling facts. Though the existence of rationalist groups would reduce this effect somewhat, I don't think this totally mitigates the "ugh, I don't want to think about that" mentality that some people have towards rationality.