I am going to get downvoted here, and WBC would say pretty nasty things about people like me. However, I have never heard anything to suggest that the Westboro Baptist Church are racist. In fact, the founder used to be civil rights lawyer, taking cases that other white attorneys won't touch.
I'm probably using out of context example here but WBC protests at dead soldiers funerals regularly, everyone knows that, and they're not touched. Though I suppose protest and direct prejudicial comments aren't in the same ballpark entirely.
It's all circumstantial I guess.