Most talk is between teacher and student, not between peers. In addition, the peer interaction taking place is often highly negative. It doesn't take thirteen years of sitting in rows to realize that when you check out at a store, you wait your turn. It doesn't take repeated insistence that there is only one right answer and talking out of turn is punishable to make someone a contributing member of society. Rather, a loving family is a model socialization laboratory.
Parents teach respectful listening by practicing it.
With adult help, children learn about conflict resolution. Younger siblings or friends help bring life to the idea that making way for the weaker is a part of being human. No one has to hear taunts about their looks or family status. And, if mean words are hurled, a loving adult helps the combatants make sense of the feelings that prompted them and that result from them. You don't get this kind of socialization anywhere else.