His hatred is shown in isolated comments and looks that he describes during Trueblood story. While the farmer is talking the I.M. describes him "cursing softly" and thinking that all his chances of success where fading away due to Trueblood´s ignorance. Our smart main character seems to be overwhelmed by the strength of the farmers story and despises the idea of the white man he is driving around to feel compassion for the ignorant rapist.
Finally, is this what happens in modern times? Is this what everybody knows as stereotype? Lets get some examples: Chilean swear, Americans are fat, Colombians do drugs and "Gallegos" are stupid. Stereotypes have ruled the world and have been always fed by racism, prejudice and most importantly social acceptance. SO, in order to lighten the mood, here is the stereotype song:

