Approaching strangers’ children without permission= Good way to get yourself in serious trouble.
And how will that trouble come? Turn of the TV? the smartphone (Justin Bieber, Miley Cyrus)? the grammar school sex education (irremedial moral influence by educators)? isolation of the children from communications technology? by brandishing your fist in the face of a person well within his/her Constitutional rights?
Or, on the other hand, perhaps by well-put rejection from the lips of the well-founded child himself or herself to strangers invading their personal ethical structure in the absence of immediate parental guidance--hmmm?