In Chapter 20 why does Mr. Raymond pretend to be drunk?

Mr. Raymond explains he feels he has to give the population some reason for his odd behavior (being friendly toward black people). Mr. Raymond believes it's easier for people to handle strangeness when they have a reason to explain it. Thus, he pretends to be a drunkard. He says he thinks that children like Dill, who is so upset over the trial, haven't lost the instinct that tells them that it's wrong for white people to "give hell" to black people without consideration for their basic humanity.