I'm surprised Hunter shot himself because he didn't seem the type. Maybe he was ill and didn't want to waste away.
Like Jack Kerouac before him, he had the ability to vividly capture the moment in his prose. You can read his books and articles, particularly his early work, and decades later it's still fresh and full of energy. You can feel the combined forces of the times in which these pieces were written and Hunter's own personality coming through in the writing. A difficult thing to do well.