Re: what is the reality of the dangers from other humans on the trail?

utahhiker,

Let us look at the episode in detail:
1/ Man seen near truck, examining everything but harming nothing (apparently).
2/ Truckowner, instead of casually walking up to stranger (who may have been only looking for water), shouts (perhaps obscenities, we don't know, but harsh words) for the stranger to get away.
3/ Stranger can't hear particulars and stays by truck, perhaps hoping hiker has water, food, etc.
4/ Truckowner shoots gun to warn stranger.
5/ Stranger, not hostile until this point, slashes two truck tires in anger/retaliation for savage behavior of truckowner (not defending vandalism - but warning shot was way out of line).

So, we don't know that the "crazy man" had malicious intent. He didn't key the truck, he didn't break a window...he did no harm until some crazy man started shooting at him. Nobody likes being taken for granted; judged just because of proximity to something, in this case.

You said:
"Besides, the dude that was wondering around out there probably has no clue about the internet, as opposed to others."

There is a big difference between being alone in the woods/ mountains and being too unsophisticated to use a computer. People who read sites such as this want to be wandering in the mountains -- but they can also navigate a computer. As for being "crazed", various forms of deeply aberrant behaviour are sometimes found among the best and brightest -- the "Hannibel Lechter" set.