Another parent's different approach raises the possibility that you've made a mistake with your child. We simply can't tolerate that because we fear that any mistake no matter how minor could have devastating consequences. So we proclaim the superiority of our own choices. We've lost sight of the fact that people have preferences.
One can know a man from his laugh and if you like a man's laugh before you know anything of him you may confidently say that he is a good man.