what makes tom kinder to the fat man?

THe fat man is a truck driver that gives Tom a lift in chapter 2. Initially the man refuses on account of a sign that says "No Riders". Tom tells him that, "a good guy" doesn't care if “some rich bastard makes him carry a sticker.” AS Tom travels with the man, he realizes that the driver has his own problems too. The driver explains how the loneliness of the job can wear a man down and all he wants to do is talk. Tom seems to understand this and is kinder to him.