Speech

Novels tend to have the happy endings of evil being triumphed because readers like to read a story in which evil does not prevail.  Readers like stories of human beings rising up together and defeating evil--or at least pushing it down for one more day.
I think that is what Faulkner was getting at with his speech, and not just about readers but about us. There is this collective desire of real goodness, however little we may act towards it at times. 
However, evil does exist in the world, and we have this almost unspoken duty to bring it to light. And that's what Faulkner does with Sanctuary.  His choice in omitting purely good deeds is interesting, and I think Ashleigh provides a neat idea with the caricature explanation.

I also have the theory that since Faulkner wrote Sanctuary twenty years before he gave his speech, and that he was younger (obviously) while writing Sanctuary than when giving his speech, that he was simply more cynical during his younger years, as we all tend to be, than when he was older and presumably wiser in his experiences with humanity.


Water cooler breakdown: However crappy things are and however many crappy people there are, there will still be good people doing good things. Because that's who we are.