Was there actually some kind of disciplining going on by Harry when he slapped Hugo.

In other words, all day long he sees Hugo being a major, visible, public pain in the ass. and a guy like him is keeping tabs on people. He sees Hugo and parents as being wrong, incompetent, lack of character and self-discipline and when Hugo kicks him the right thing to do seems to be to give Hugo a slap, in front over everyone that is not too bad, but serious enough for Hugo and his parents to get the message. Instead of getting the message, people like Hugo's parents seek to validate their self-centered view of the world.

I have to wonder why these girls are even friends, and what is the limit on supporting your friends in situations there they are wrong, or maybe not wrong, but not very right.

Friendship and even family should not be a lie, cheat or steal for, option.