I'm a bit nerdy. So, sometimes, I will refer to myself as a nerd. This is a bit ironic and self-defamatory, so it's cool. It's not offensive. If a big football player went up to me and said "Ah, what a nerd!", there's no way that that can come off as non-offensive. Is that a "hypocritical double standard"? Similarly, rednecks often ironically refer to themselves as rednecks, and gay people often call themselves "faggots". It is ironic, funny, and hence, not insulting. However, in no universe would I, after observing this behavior, expect to be able to go up to a redneck and say "You're a stupid redneck", or a gay person and say "LOL faggot". Nor do I consider myself the victim of some horrendous oppression because of this.
The N-word is, of course, an extreme example of this. The offensiveness of slurs is directly related to how a subculture is perceived by the dominant social class. So, there's pretty much nothing you can say that can seriously offend a white person, because they're the dominant class. There aren't slurs (that can be taken seriously) for Muslim in Saudi Arabia either. Black people, on the other hand, have historically been the bottom of the bunch. So the word associated with them has incredibly offensive connotations. Redneck and nerd aren't awful in a social setting, faggot is something that you need to keep from saying in this day and age, and the N-word is basically a swear. In the logic of comedy, however, this actually makes it all the better when used by someone who the slur would typically be directed against. But there isn't any way you can say it without being offensive. I am sorry. This is reality.
It's just incredible to even try to imagine the sort of logical contortions you must go through to justify this level of privilege blindness. Apparently we must put our hands over our eyes and pretend that social class doesn't exist; However, in regards to some negative things which we all know exist, such as the fact that blacks are naturally less intelligent + criminals, well, it's equally wrong to frown at intellectual pursuit in regards to those worthy subjects. It's completely and totally backwards that blacks should be able to ironically insu.lt themselves when I can't insult them as well.