Exactly. It's a cultural thing, predominantly a young, black male, urban, hip-hop culture. But you said "black people" in your original post, and not a particular demographic. You explained what you really meant and it's obvious you didn't mean to offend, so, no offense taken.
I agree it was stupid of the author to focus on that, but to imply that he would have done differently had he "hung out with black people" is equally ignorant. What if he hung out with Mayor Coleman, Gene Smith, the President, Cameron Heyward, Mike Doss, etc. etc.? All black people don't use that word.