Snatch Violence can be necessary.
There is a classic screenwriting axiom that states that if you introduce a minor character, making him a decent fellow in walking an old lady across the street or give him a sweet gesture through a less hackneyed construct, the advisable thing to do is to kill the character off immediately. In doing so, the audience will care about the character and the reaction to his death will resonate throughout the theatre. In Sergio Leone's hands, aided by Ennio Morricone's magnificent score, this very conventional plot device becomes something quite operatic and moving. We see the shadowy figure who victimized this family and the camera dollies around to hold on a cold, impassive face. And the audience immediately detests the antagonist for such a cold-blooded act, pining for his inevitable death.