I've learned that there is often no telling in advance what many of "those places" are. You could be driving to a 4th of July fireworks celebration in an area that you never thought was a bad area and suddenly find yourself in an all out riot.
Stay as long as you can, photograph what you can. Be sure any hostile people from the crowd knows you are armed and are not afraid to defend yourself.
The only scenario I can think of is if you are caught in something like a riot or something along those lines. When there are crowds of thousands that don't look like you, and hate people that do happen to look like you. You will most certainly have to flee in that case
Just ask the people living near Ferguson, Missouri how quickly that bubble can expand.....oh lawd!
you live in a very unique bubble.