I have a few things to say about it myself. This has not been covered because a certain distraction has prevented this thread from evolving into constructive commentary. Let me take care of it for you, and then, we'll carry on.
Many years ago a JW mother and her little boy came to my door. The kid opened up with "bad things going on in the world" and I said something like "you shouldn't be worrying about things like that. And besides, haven't you been told that children should be seen and not heard?"
I am sure he didn't know what the heck I meant. His mother did not seem too bright comprehending it either. But I went on to say something to her about it being improper for a child to usurp authority over an adult.
Since the JWs believe that a woman is not to teach or instruct, how much more ludicrous is it to send a child to prostelitize to adult strangers? They don't even know what they are doing! This kid was probably about 7 years old.
Perhaps if when we encountered such situations we could say something to put the parents in their place. And also something to the child to make him realize something is not right...like "why aren't you watching cartoons this morning? or building a tree-house? Or at the playground with the other children?" Maybe just maybe those words will ring to him and come to mind later when he is thinking about life.