good question. People are hassled everyday and even killed, but if you try to purposely put yourself in that situation, it'll never happen. It's just too rare. Most people in the back country or in parks are plain nice folks who're tripping over themselves to help out in any way.
I've traveled alone in many countries without ever having a single problem with hooligans. Of course my beard was down to my navel, and my hair below my shoulders, and I carried more dirt than could accidentally get on me. People left me alone though.
Where exactly, was I - you ask. Well, Norway, and all European countries south, Colombia (evilest country in the world), Nepal, China, Pacific rim, South Sea islands, Thailand, Canada and of course, U.S. with all of its bikers, drugees, low-lifes, quasi-cops, and . . . self-important National Park rangers.
There are snakes, spiders, wolves, cougars, bears, skunks, rabid bats, wild boars, gators, scorpions, and moose (I was almost killed by a moose), but the most frightening, deceitful, cunning, and by far the most threatening is the . . . fellow human. Beware, but be not afraid.