Thoreau's quote sums up Chris McCandless' attitude towards his parents. It says, "I sat at a table where were rich food and wine in abundance...but sincerity and truth were not...the hospitality was as cold as the ices" (Ch.12).
Chris had been "raised in...comfortable upper-middle-class environs" (Ch.3). From all accounts, his parents raised him well, providing a good home, education, and positive attention. Yet Chris harbored deep resentment towards them, which was acerbated but not soley caused by his discovery that his father had had a child by his former wife after Chris was born. Chris went through a period of "outrage over injustice in the world at large" (Ch.12), and his parents became symbols of the materialistic values he despised. He scorned the things they tried to give him, thinking that they were trying to (buy) (his) respect" (Ch.3); he essentially wanted nothing to do with them, and shut them out of his life.
Although "many aspects of (his) personality baffled (them)" (Ch.12), Chris' parents seemed to truly care for him. Although his father was "accustomed to calling the shots" (Ch.11), and his sister also clashed with their parents during her adolescence, the parents tried to adjust and reach out to their recalcitrant son, but were always rebuffed. It would appear that Chris's animosity towards his parents was grossly out of line, even considering their shortcomings.