I can honestly say, that in the 12+ years when I hitchiked around the planet, I have never had a bad experience with a driver.
Whatever bad shit I encountered was always when i wasn't riding in cars.
I was of course propositioned by countless gay men, but coming from a culture where homosexuals (mostly) aren't vilified, that never bothered me any.
I cannot count the times someone have taken a detour, just to show this foreign guy, visiting their country, a nice place.
Like when Burnham took a day out to show me around Mt. Hood. I wasn't hitchhiking then, but it was the same generosity.
I always pick up hithhikers in Europe, I have a huge amount of payback to work on.
In the US I check them out, and if they look too scruffy, I pass them.
Not out of fear but because I find it impolite to stink another man's car up, just because you can't be bothered with keeping yourself clean.