[–] MrSaxoBeetus 0 points 1 point 1 point (+1|-0) ago
Basically, because they were black activists, and the (de)construction of the image of the black body in Western societies and is a huge deal for the black movement. Some SJWs, in order to disqualify people they disagree with, label every person that find a white individual attractive as a racist. So, if you are a black activist that happen to marry a white person, you're racist despite of all the study, time, money, and work invested towards the black movement ideals.
I kinda figured you were being ironic because this thought seemed absurd to you, and yet it happens non-ironically every day in Tumblr, Reddit, and Facebook.