The fact that such marches, (and other, more tangible work) do not command the same attention as the demonstrations that arise when people are killed by public servants does not mean that they do not occur. Members of these afflicted communities are working hard, and consistently, to do what they can to address the violence and lack of hope in their communities.  Outside of these communities, it's difficult to know what is actually going on. What's easiest to notice is  naturally enough what the news likes to cover -- police shootings, protests, the destruction of property by a minority of protesters, and the crushing statistics about young people shooting each-other.  
All the best, xoxo