This is a wonderful thread, so affirming.
The technician when I went for my 13 week ultrasound made a point of telling us how well we interacted with our kids, and what a lovely family we are (having some major issues with DS4 currently, so it was lovely to hear).
In the city around Christmas time we came across a young boy who was lost, absolutely distraught. I got my kids to talk to him, because he was obviously freaking out about adults, and my DH went and found a cop. The mum turned up after about five minutes. We were walking away, and the two roughest girls imaginable (piercings, tatts, makeup sooooo thick) walked up to us and said how nice we were for taking the time to wait with him when everyone else was too busy or too worried about getting in trouble. Just goes to show you really can't tell!
We've had teens in Macca's and places like that give the kids their happy meal toys. And when my son dropped his ice cream recently the girl (maybe 16yo) behind the counter noticed. I was lined up to buy another one, and she came out with a fresh one, gratis, and said she'd be right over to clean up the mess.