[Retra]

The reason I am willing to attribute it directly to religion is because there's a kind of 'natural selection' that goes on with regards to people's religious attention such that those who practice their religion exclusively in private end up being those that practice dying religions (as they can't effectively compete for mindshare against those that proselytize.) Obviously that's only an approximation, but even so it is a pretty good one, as it is not a coincidence that the spread of specific religions correlates with promotion of public religious practice.

Most religions will associate the promotion of their religion as a good deed, and they are willing to overlook many bad deeds that lead to it for those reasons.