My normal reaction is "Oh, poor dear, you are so charming even with your face scrunched up! Come live with me and I will cuddle you and pinch your cheeks and buy you tiny child-sized things."
Today it was "WHY IS THAT MOTHER NOT YELLING AT HER CHILD WHO IS HORRIBLY MISBEHAVING?!"
In France, disciplining your child in public shows you are doing your job as a parent. In the US, you are publicly humiliating him/her and permanently destroying a fragile ego. I exaggerate, but only a smidge.