It is entirely possible that someone who thinks AAE is bad english just happens to be wrong because they don't know or get the specific details. If this is some easy issue everyone should be able to grasp, then why do they hand out degrees in linguistics? Your assuming racism is automatically the reason for people having that opinion is like me calling people Luddites when they object to demoting Pluto from planetary status. It wouldn't matter if 99% of Luddites agreed with them either, doesn't automatically make them one. Same, being racist probably inclines people to think AAE is bad english, does not mean people who oncur are also racist. That's a heck of an insult to be chucking around at people.