I wonder if part of the reason for peoples responses to the situation is where you live. I live in a rural area and we tend to help each other first whether we know you or not and worry about authority figures later.
We are somewhat of a fear based culture and if you watch too much news where you hear of much of the evil that goes on throughout the world you can start to think it is much more prevalent than it actually is on a per capita basis.
I find that almost all people are good and decent and that parents can lose track of children even in the house very easily.
I would have done the same as you bailsmom, but I wouldn't have felt uncomfortable afterwards. I would think the father would have been so scared about what could have happened to his daughter that he would be scared to let her out of his sight for quite a while.
"Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it's the only thing that ever has."--Margaret Mead