Maybe the default is disconnected beliefs and actions driven by imitation. New religions tell people that they shouldn't base their actions on imitation of their local authorities, forcing them back on nominal beliefs and forcing them to make inferences.

Why don't they just imitate the missionary? Surely, the missionary communicates "be like me," not "be different from them"? I guess it could be only the over-verbal converts who notice that menstruating women have cooties. They might make good stories without being representative. But there is the general principle that converts are more observant; are they radically more observant, or do they merely find more observant people to imitate? (if the latter, why?)