As a white dude married to a Mexican gal (no pics) I've witnessed and experienced racism like this, but not to this extreme. Unfortunately this kind of attitude is not all that uncommon. We were at Dillard's once and I was pushing the stroller on the other side of the aisle when one fo the employees (an older woman) suggested my wife shop in another section until they could get more people there (presumably to keep an eye on her). I wonder how her attitude shifted after it became clear that I was with her.
Another instance, we were in Jasper, Arkansas at a rock climbing destination and went into town for a meal. Everything was great and we had good service until a few old guys got seated across from us. Our server never came around again. Best we could figure she was afraid of what they would say or think. I ended up having to go up to the hostess and asking for our bill just so we could leave.
I'm not sure what I'm getting at, other than if you are a typical white guy who doesn't care about skin color you don't get exposed to racism much, and it is easy to think that it is something for history books. It ain't. But as someone who never had to deal with any of this due to white privilege or whatever you want to call it, it's kinda like trying to hit an unexpected curveball.