Marching allows people to vent anger, frustrations and disappointments. There have been hundreds of marches on the south and west sides of Chicago condemning, denouncing and damning faceless shooters, gutless public officials who also march-up-a-storm and inanimate objects drawn in a circle with a red bar through them - Guns. Murders continue unabated.
Orwell, in 1984, called such venting "The Two Minute Hate," Which allowed the opporessed to direct their anger, frustrations and disappoinbtments at faceless enemies, caricatures of enemies and inanimate objects and away from the oppresive totalitarian regimes defining each person according to needs of government.
Today, too many people, particularly young people, who spend most of their waking hours 'thumbing' human contact via a Steve Jobs product, who largely ignore their family, friends and fellow citizens due to addictions to cellphones, smart-phones, tablets, and keyboards need an opportunity let the world know just how feeling and human they happen to be -in solidarity with strangers who trying to get home to their kids on west and south sides.
Know this - the crowds of earnest, breathless and obnoxious white suburban hipsters blocking traffic here and elsewhere are cattle and chattle of CPUSA.