Yes, we tsk-tsk and shake our heads. This is the very point: there are things that can be legally regulated, and there are things that can't. It ultimately depends on the system of values, and on how much people want to integrate: what is universally considered comme il faut, and how desirable it is for a person to follow it. There's no other way to make people behave themselves. If it pays to be nice, people will tend to be nice. If it doesn't - if their reference group thinks that swearing in front of kids is cool, and it's their reference group that provides guidelines for society - no number of arrests, finings, etc will change anything, except deepen the abyss between those few (and fewer) who want to be nice and those many (and growing in number) who bully them around. If we want to break this tendency, society should learn to use subtler mechanisms.