Indeed, this is the first reason given. But it is not the only reason. Nor must they obey this commandment of God because they fear dad's punishment. Chastisement is a deterrent to disobedience, but it certainly is not the reason for obedience. And yet it is not infrequent that this is the reason given by children.
Children honor their parents because they are thankful.
Children, love your parents because you are thankful to God for everything they are for you. Especially, they must honor their parents because their parents are over them in the place of God. Children, obey your parents in the Lord . . . These reason show how serious dishonor is. First, dishonor shows that children are not thankful to their parents, and do not love their parents.