[reducesuffering]

> but nobody was hurt

You actually have zero idea who or how people were hurt because this is one side from Feynman. It's bad for the same reason that a goal of making lots of new friends and then backstabbing them is bad. Sure, it can be highly successful to making new friends. Not so long term beneficial, friendly, or moral though...

[Dig1t]

He said that he would get verbal agreement to sleep together before buying drinks.

How is getting consent to have sex and then later having sex equivalent to stabbing a friend in the back? I don’t understand the analogy.

Unless you think one-night stands are morally wrong, I don’t really see any problems with his actions.