We've set up a terrible system - where it's always incumbent upon the oppressed community to "say they care" in an acceptable way after and during state-sponsored abuse. ['State-sponsored abuse' isn't my term, it's the New York Times'.] That's a trap. Candlelight vigils don't get attention. Riots do, and looting is a byproduct of riots, and I'm tempted to drop that one MLK quote here.
America loves itself some riots and looting, when the right folks are doing it. Tut-tutting the minority of looters when there's a huge majority of nonviolent, non-looting protesters is a derail. A cheap, smug way to duck out of looking in the mirror.
None of the people who I saw share Roberts' photo had posted about Ferguson before.