Having lived in the American south for a good part of my life, I've seen all kinds of 'old fashioned' racism, sexism, etc. All of the cities around where I grew up were still pretty damn segregated, despite it being the 90s, and of course we're also talking about the Bible Belt as well. I always felt completely comfortable joking with black friends about something stupid like chicken and watermelon, but that was because they knew I'd be the first to stand up for them if it came down to it. And that might sound like an exaggeration or something, but shit was pretty damn real. When I was in 7th grade a white kid shot a black kid at the middle school of the next town over. My middle school, meanwhile, was in the 'black section' of town (it was the old black high school), and everyone was acutely aware of the racial tension. I remember being pretty damn scared something would happen for a few weeks after the shooting, and it certainly didn't help knowing there were three separate cases of kids bringing guns to the school in the year before that. Luckily there was a panic among parents all around the county and they implemented actual security measures for the first time ever.

Long story short, there's a huge difference between a bunch of white guys gathered together cracking jokes where the punchline is "stupid niggers", and the kind of good-natured joking I mentioned before. It's all about context. Even saying "nigger" (which is the 'worst' word in my mind) doesn't really mean anything unless there's some context involved. That's the point comedians like George Carlin were trying to make.