Yeah, this one is pretty easily explained as a statistical artifact in this way. The more religious someone is, the more time they are likely to spend around other religious people (at church, with friends met via church, various knock on effects of these things). As you become more religious, this effect will tend to increase your estimate of the population's average religiosity.
This also explains a number of political effects, especially once you start looking for it in other high time commitment social activities.
This also explains a number of political effects, especially once you start looking for it in other high time commitment social activities.