Unfortunately you are trying to compare words that fall under the same category of being demeaning , but carry much heavier weight. To argue that the N word is on the same level as cracker is a tough one. Not that it is right but the word has the ability to level someone. I have heard it used before as many have here and it makes my stomach turn. If a black guy is calling people crackers I would argue that they are racist, but we all know the word carries much less weight based on the history between the races.
The whole he has black friends argument does not mean is isn't racist, but that he was in a situation to get to know these people and saw beyond their skin color. Either way he still harbors some sort of hatred or fear to continue to use such a hurtful and offensive word.
As for people using the word fag. I would say this. Unfortunately that word took on a different connotation in the 90,s where it was unabashedly used by men to poke fun at each other. This desensitized some to it, and it flies out of their mouths like nothing. I would say this about Kobe, he isn't necessarily a homophobe for saying it then, but if he still says it now he is an intolerant jerk, who very well may be.
Point being all of these worlds have different origins, but you may notice there is one word none of us have actually written out, instead referred to as the N word. It carries too heavy of a weight for a white person to bandy about without that person carrying some form of hatred.