Here is the problem with your analogy. A police officer/security guard is paid to do that. That is their job. What you are asking of men with families to support is to risk their lives for someone who quite possible could be the very cause of the encounter you see happening.Depending on the situation, I'd say most wives and children would be honored to say that their father/husband died doing the right noble thing showing a display of courage to stand up for people who can't help themselves.
Similar to a police officer or security guard who dies defending or saving someone's life, the only difference is that they have authority but still the same outcome.
It'd be sad and tragic but at the same time he'd be somewhat of a hero and celebrated in the eyes of many, it just depends on the hows and whys that led to his death.
At the end of the day, it takes heart, courage, and complete mental toughness to intervene in any situation so I can understand if some men just aren't up to the task for reasons mentioned, among other things because it's not an easy thing to do for anybody.
A married man's loyalties should be to his wife, children, family, and friends. Only a fool is out here jumping into situations to defend the honor of someone when they have no clue if that person is innocent or not. What a smart man does is call in the ones whom are paid to do that (Police/Security), and then go back to protecting their own family.
Feelings of pride do not pay bills, do not raise children, do not comfort wives, do not do anything but give a short term mental boost. After that, the reality of the loss sinks in, because that loss can be catastrophic to the wellbeing of the family. When you have people that depend on you, you make sure you honor your obligations to them first.