Leon, while personally endorsing your views, we don't live in a society that in general would get involved. Not through cowardice or lack of moral compass but through a general conception that
a. someone will deal with it and
b. an underlying fear that if they do get involved they may have questions to answer in court.
A good friend of mine broke a boy's nose when he heard a commotion outside of his house. Turns out it was just a boy and his girlfiend larking around. Boy's parents tried to nail him to the wall. He now has GBH on his record and was lucky not to go to jail.
I think that most people think twice these days before 'getting involved.'