Travis desperately tries to assist a young prostitute. While he performs several depraved acts over the course of the film, he retains an internal moral compass guided by his own system. On the one hand, he is perfectly fine murdering unarmed civilians; on the other hand, he can't bear to witness Iris continue to work as a prostitute.
While at an amusement park, Nick explains to his son, Joey, that one needs moral flexibility in order to perform his job as a lobbyist. He then explains how to argue effectively and in a manner that results in him always being right. He demonstrates this technique in an argument with Joey in which he asserts that vanilla ice cream is the best.
Eddy commits an unselfish deed by replacing a dead bulb on a Christmas tree, prompting Santa to deliver presents to all of the kids in the cul-de-sac. It is clear that one selfless act isn't enough to change his character, however, as he takes everyone's presents for himself.