Once again, you are talking out of your ass. Remember the case in Sac where the guy killed his son?
I remember it, because he had a blue 4Runner and was headed north that day. I happened to be heading north in a grey 4Runner. Every cop between here and Bend ran my plate.![]()
Every cop, sure.
Personally, I'm a little skeptical on the benefit of blasting these out to every phone in the vicinity.
Given mobile penetration, you can reasonably assume that the abductor now knows exactly when LE is going to start looking for them. (i.e. that it's time to ditch that vehicle or plates or find somewhere to hide.)

and annoyance a couple times a year if it helps get somebody's kid back home safely.