People care, because they come to the internet, or come to play games for an escape from real world stresses. People encounter racism / sexism / whatever in lots of places already, and far more frequently than you may think they do, and have this silly idea that games should be a place to for fun, free of that sort of thing.
Saying, "it's the internet" is a stupid, lazy answer, because "the internet" and "real life" aren't separate anymore. People's social lives are "the internet" plus "real life" - the artificial divide between them is collapsing, and that's a good thing. Or at least it will be once communities start putting their houses in order and policing the asshats.
That can't be done just from on high - it requires people to do more than just ignore unacceptable language, it requires normal, moderate people who don't suffer from racist / sexist etc language, to show empathy for their fellow humans and stand together with those who are hurt by it and call out the asshats whenever they do it. Make a scene of it. Get others to make a scene. Eventually the "n-word" and similar slurs will be considered unacceptable in the gaming sphere in the same way it is in most public spheres. As it should be.
This is exactly what I think. I'm not for internet police or anything like that,I just wish there was a much greater sense of social responsibility online. If people started throwing these insults around on a bus/train/in a pub they'd soon get shot down and shamed for the idiotic fools they are and rightly so.
This notion of "it's the internet, deal with it" is quite frankly, pathetic. There is no disconnect between real life and the web these days, especially when it comes to social circles. It's no wonder there's a proliferation of self-entitled, socially irresponsible, disrespective little *******s around these days.
The internet community needs to police itself. Why should be a safe haven for bigoted little keyboard warriors to vent their spleens?