> Strangers, even unvetted ones, almost never pose a danger to children. The vast majority of harm done to children is done by friends and family. Having more strangers around makes your kids safer, if anything.

I hear this a lot and my guess is this is simply a function of how much time family and friends spend with a child (in relative privacy) compared to complete strangers. The surface area of attack is way smaller for random people; they don't have the "reasonable" opportunity.