I have a dog who is great with children, she loves them and would never do anything untoward to a child who comes up and says hello... HOWEVER after being in the park Saturday, I had 6 (!!) different children just come up and stroke my dog. (we were sat having a coffee and my dog was sitting behind my chair in the shade so very easy to sneak up behind me and say hello!)
It's all very well for a dog like mine- however I've had rescues before who may not have been so happy about it, and to be honest, ANY dog could snap if taken by surprise?!
AIBU to think that you should teach children to ask if it's ok before going full steam ahead and stroking a strangers dog?!