I saw a video on the Cenk Uygur show, edit: here's a link to the video:
http://tarawallis.tumblr.com/
This shows better than a lot of stories can tell about culture.
The parents of the 17 year old killed in Florida were being interviewed, apparently by local media. It was a somber interview, the mother tearful.
A reporter asked the mother to describe her son's demeanor usually. She said he was happy, liked to listen to music, talk on the phone, to girls, watch sports... to eat...
At this point another reporter interjected:
"Chicken?"
There seemed to be a snickering among reporters. The parents didn't seem to notice the racism, and a man (father?) said 'yes, whatever was in the fridge'.
That's just outrageous behavior. No one called the reporter on it, said anything at the time.
But I think it helps show how there are different cultures - that while we might have a hard time imagining such behavior, somewhere else it might be not surprising.
For a reporter to say such an offensive, racial 'joke' to a tearful mother about the son who was just killed... and then we ask about the culture where there's a question whether there's racism playing a role in the investigation of a white shooting a black boy, it adds some understanding of the possibility. When a white witness says she has made many calls to the police to tell her story and that she does not think it was self defense and that they refuse to talk to her, while the police put out a false statement that they had talked to her.
It's also easy to imagine how this story could easily have not gone anywhere if for some reason the national media had not decided to publicize it.