Clover is also equally changeable but she's not the one that people pick to do this to, generally. Does it make them racist? Depends on your definition.
You completely missed my point. Apparently a lot of people like Cross more than Clover. Bethesda made the Brotherhood look like end all knights in shinning armor, so people are going to be attracted to that. There's a companion that's in the Brotherhood? AWESOME! But wait...maybe I should change her to be more attractive to me. Uh oh, I'm racist!?!?!?!?
Like I said before, I can't believe you're jumping to this conclusion.