A lot of kids waffle between looking up to their parents as heroes, and viewing them as embarrassing older people who are out of touch and constantly bossing them around. This type of binary thinking can make it downright shocking for a child to see their parent exhibit bravery or skills not normally needed.
While parents are just people who had whole lives before raising families, it's easy for kids to forget that, so when mom or dad show off their ability to break up a fight or handle a crisis, it can be downright awe inspiring.
My Dad was driving me to his office when I was about 10. There was a group of 5 people outside of the library kicking the sh*t out of this guy's face. My Dad just calmly parked the car, got out, and started pulling these dudes off this other guy like it wasn't even a thing. Someone called the police while my Dad held them all off.