My purpose was to initiate discussion.
My take away is more of a "why people think the way they do", than a deep analysis of population density by demographic. (I'll also point out that this wasn't a simple analysis of hate crimes against black people, but against any group identity (whites, Hispanics, women, gays, Jews, etc.)
I'm advancing the idea there are more bigots doing bigoted things in urban centers, which is perhaps why people in urban centers view this as a problem; where as people in rural areas see these sorts of events so infrequently that they view them as very isolated incidents and a non-problem.