Jon Krakauer said this quote

It is hardly unusual for a young man to be drawn to a pursuit considered reckless by his elders; engaging in risky behavior is a rite of passage in our culture no less than in most others. Danger has always held a certain allure. That, in large part, is why so many teenagers drive too fast and drink too much and take too many drugs, why it has always been so easy for nations to recruit young men to go to war. It can be argued that youthful derring-do is in fact evolutionarily adaptive, a behavior encoded in our genes. McCandless, in his fashion, merely took risk-taking to its logical extreme.