Agree! -- well, mostly.

It's nothing to do about gender, I think it's about bad humanity or good humanity, self-control sort of thing. There are bad men, there are bad women -- the jails keep some of them, both men and women. I think that stranger did exactly the right thing, he helped maintain a safe and decent public order, and helped prevent a potential harmful domestic conflict. Whether that couple will stay in their marriage, that's their business, nobody else cares. Whether the arrested feels good about it, that's his/her business, nobody else cares -- at least one thing has been made sure: that public misconduct has been stopped, that potentially harmful domestic conflict has been paid attention to.