Yeah, but bringing up Grizzly Man is useful exactly for that. Plenty of people want to say Steve Irwin was killed because of his insanity around wild animals. You know, "I called it, saw that crazy fool getting his ribs cracked by a huge female croc, and I knew his insanity would cost him his life". That's also why the story has "Traction" in the news industry.
The guy wasn't insane. Treadwell was insane (or, some would say, stupid). He got so wrapped up with his bears that, at the end, with an invalid air ticket home, he couldn't deal with what he called "the human world", and rather than sort out his trip, he went back; all his "Friends" had hibernated, and he was left with the other desperate outcasts.
It makes a great story -- a man whose obsessive insanity drives him from civilization and to his ruin; it's also pretty much the plot line of every Werner Herzog film ever made. But this one is the best.