Children should acknowledge other people, saying 'hello,' 'good morning,' 'goodbye'. They should understand that there are times to sit down and be quiet. That's a prerequisite for school. They also need a respect for authority, the lack of which is a tremendous handicap in school.
If you go back in time you'll find tribes that were essentially only concerned with their own tribal members. If you were a member of another tribe, you could be killed with impunity.
