How does Krakauer portray McCandless as a non-conformist in this part of his book? (aversion to rules, materialism, etc)

Throughout his life, Chris shows natural talent in many things, but always a strong resistance to being coached. He would get very skilled at different sports, but always refuses to follow instructions that could take him that last bit further to greatness. Even in high school McCandless is caught up in serious questions, becoming obsessed with fighting racial oppression in South Africa, and spending weekends in the seedier neighborhoods of Washington, D.C., talking to prostitutes and homeless people, buying them food and giving them earnest advice on how they can improve their lives. One time he even brings a homeless person home with him and secretly sets him up in the trailer his parents have beside their house.