This is one method to ensure impregnation
Haha
But I'm a bit confused by your argument. Are you saying that this happened only in the past, and that this type of event "selected" believers to a degree that a significant part of the population became believers?
Or are you saying this kind of thing still goes on today?
And if it's not still going on today, do you think there's an evolutionary advantage religion to religion today? If so, what's the mechanism?