NASCAR might not be "all" White, but NASCAR is anything but diverse.  Its a "sport" who largest fan base is based in the South, and you can easily see that the overwhelming majority of its drivers and fans are white.  They also still fly the Confederate flag at events.

The NHL has a similar issue in that the vast majority of its players are White - however, the NHL does not have the same issue with lack of diversity in its fan base.  The NHL also doesnt fly the Confederate flag at its events.

Personally, I have never watched NASCAR as it seems more boring than golf (and that takes A LOT).  I really couldnt care less about it.  The fact that its "family owned and operated" means literally nothing to me.  The NFL owners are all American Citizens as well - many by famalies.  Im all about supporting American businesses, but im not going to just support a business because the President says so, or because the business is "American".