Because many of them are afraid that if they did, THEY would have to spend some time in fields of cotton, rice or sugar cane, doing the back-breaking labor themselves--and maybe the profits would go to recompense the descendants of slaves. They can't imagine more than having the tables turned and payback time would (will?) show that they're no better than anyone else after all. And then there might be mass suicide as these creeps would find that last utterly insupportable. For which, God forgive me, I wouldn't shed a single tear. And I am also a paleface in his sixties.