In modern times there's a total of about 70 child kidnappings per year in the US. I am excluding parental kidnappings which sends that up by orders of magnitude, but I think that's fair because that's an entirely different issue and you specifically said stranger anyhow (though even of those 70 - a sizable chunk are not strangers). For contrast about 400 people are struck by lightning each year.

Statistically, it just doesn't happen. It's just one of those things, like terrorism or mass shootings, that is so unbelievably terrifying that people overreact in a self destructive way to try to prevent something that is statistically much less of a threat than just normal behaviors we take for granted.

I don't think money is the key issue. There were no clubs or nice tracks when I grew up, but ditches, canals, and forested areas worked just as well.