I would think the point would be, that if you are in unfamiliar territory, you would not have the local knowledge that would enable you to avoid bad places. Years ago, I was attending a conference in Boston, a nice scholarly meeting on historic preservation. For some reason, I walked to one of the sessions, thereby traversing Boston's Combat Zone, about which I knew nothing. It was not your typical walk in the park....
Locally, I know the bad spots to avoid and on what streets your car will drive away without you. In a new city, not so much. As a visiter, I'd value information, even of less then perfect reliability, on these spots.