If an uninvited stranger touched my face, ruffled my hair and patted me on the head, I would go for them, because it's assault.
What if a male stranger did that to your child and added a pat on their backside when they seemed friendly? Would that be OK?
I'm thoroughly sick of people who know better than me when I'm walking a dog.
Boxing Day, had a dog sitting facing me being trained to ignore others.
Walking towards us, four elderly people with three tiny teacup like dogs on leads. Over they come.
"They just want to say hello."
"Better not as I don't know this dog well and I'm training him to ignore."
"Oh he's fine, I can tell", as the women sticks her hand in my very apprehensive dog's face.
I pulled him away and heard this woman say loudly, "He was fine, his tail was wagging. She just doesn't want him near other dogs, only wants a people dog."
Often a young women with a working type Lab walks past when he's sitting and says thanks. She gets it.
Do not stick your hand in an unknown dog's face unless its owner says that is ok. The last time that happened to the dog may have been to hit it. You don't know the dog's history and teach your kids that too.
A wagging tail doesn't mean the dog is friendly either.