As mentioned a few times before, if a man does not respond, she will believe she is dealing with an idiot who can be INSULTED and be TAKEN ADVANTAGE OF. If a man does not respond, it gives her the opportunity to tell society "this guy is such a loser, you can insult him, put him down, and he will just take it," If a man does not respond, she is laughing behind his back and have evidence that he is a "poor excuse for a man."
I think the confusion lies between romantic and regular relationships.
If the girl refuses the man SEX, YES, act confused, smile and walk away. No response.
In any other situation, a response is warranted. Sometimes harshly.
I literally don't know how men can "walk away" when a girl INSULTS them. They wouldn't walk away if a guy insults them, but when a girl does it its different? Once you have double standards, you are letting the girl control your actions too.