Cause it wasn’t “their” daughters. Remember, those same guys would fuck any other man’s daughter and expect it to be okay. They lack the mental skills to understand another person’s perspective.
Tangentially related, it bothers me people say things like “I have a daughter so I get why it’s upsetting” or whatever. It implies they wouldn’t be able to empathize if they didn’t have one. I know that’s not necessarily always the intention, but it just rubs me the wrong way.
I was more going for the split personalities concept. The same person can say they will kill you if you touch their daughter, but then sit down with their buddies and a beer and relive how heroic they were that one time with mary joe when they got caught and her father peppered the tailgate of his truck as he sped away. Pretty sure there are popular songs about the later. So it’s okay if they do it, but not if someone does it to them and theirs.