Nope ... some people are just nasty. Nasty comes in all colors, although I think it's at least as much a gender thing as a color thing. As for the claim cited in the last line -- I was raised in an extremely racist family in the Deep South. Sorry to say, I've heard that a few times, mostly from my father and grandfather, folks of the older generation. Then I got to know some Black people and found out otherwise. I also found out that some Black people say we white folks are nasty. I have to admit there's a basis for that, especially with some white celebs and CEO's bragging about how they don't wash themselves, their kids, or their jeans. UGH -- TMI!
I think maybe the tradition of white people not bathing / showering as much may come from our cold climate origins. In the past, before we knew about germs, it was commonly believed that some illnesses were caused by being cold and wet. I've run into a few people who still believe this, mostly older and less-educated people. There may even be a grain of truth to this, in that being cold and wet stresses one's immune system so that it can't fight off disease germs as well. Especially if one is cold, wet, and dirty. (Hmmm... sounds like a good hook line for breakup song! Where's my guitar ...)