1. The Confederate flag is hardly a symbol of hate, The Confederate States of America was not formed because the white people there hated blacks, their economies relied on slave labour so they had a lot to lose financially, at least the movers and shakers did, those who actually fought in the war generally joined to protect their homes and families from Union retaliation, which I believe to have been a story point in Juarez, and was the case for Robert E. Lee. The hate started afterwards, they probably felt that the blacks were just staying around to spite them, one thing led to another and now we have the KKK.
2. Of course their are black zombies in a zombie game set in New Orleans, if that weren't possible the whole post Katrina Kanye West thing wouldn't have happened. As for RE5, well, it's Africa, there are alot of Africans in Africa, they tend to be black, so I would imagine that in a horde of African Zombies there would be quite a few black victims.
Knowing is half the battle folks, his accusations of racism, at least the ones I am aware of, can be easily explained away by a little bit of history or logistics based logic.
EDIT: To any former EGM customers, do any of you remember that one letter that claimed Rock Band was racist? The next issue had only two of apparently many responses calling the jackass out. The grounds for the accusation was that the game kept true to it's namesake and only had rock music. How was this racist? Apparently only white people listen to Rock music and other races were jilted because no rap or soul music was included, and therefore black and hispanic people were discriminated against.