In the novel To Kill a Mockingbird, what kinds of interactions do the minor characters have with the protagonist that are important? Please give...

When Jem invites Walter Cunningham Jr. to dinner, Scout learns a few things. Jem is cordial with Walter. And when they get home, Atticus treats him like an equal: 

While Walter piled food on his plate, he and Atticus talked together like two men, to the wonderment of Jem and me. Atticus was expounding upon farm problems when Walter interrupted to ask if there was any molasses in the house. 

Despite these two brief lessons,...

When Jem invites Walter Cunningham Jr. to dinner, Scout learns a few things. Jem is cordial with Walter. And when they get home, Atticus treats him like an equal: 

While Walter piled food on his plate, he and Atticus talked together like two men, to the wonderment of Jem and me. Atticus was expounding upon farm problems when Walter interrupted to ask if there was any molasses in the house. 

Despite these two brief lessons, Scout is still thinking that Walter is "just a Cunningham" and therefore, less of a person than a Finch, for example. When Walter starts eating, she criticizes him and Cal scolds her. Cal notes that even if the Finches are of a higher social class, that is irrelevant and Scout should treat everyone with respect: 

"Yo‘ folks might be better’n the Cunninghams but it don’t count for nothin’ the way you’re disgracin‘ ’em—if you can’t act fit to eat at the table you can just set here and eat in the kitchen!" 

But this lesson does stay with Scout. Much later, in Chapter 15, Scout tries to employ the same strategies with Walter Cunningham Sr. She tries to be friendly and talk to him about his interests. Walter and a mob have come to the courthouse to get Tom Robinson. Atticus is guarding the jail. When a confrontation ensues, Scout, Jem, and Dill interrupt. Jem refuses to leave. To interject, Scout tries talking to Walter Sr. about entailments. She also tells him to tell Walter Jr. hello from her. This gesture gets through to Walter Sr. and he calls off the mob. 

In Chapter 20, Scout learns that Dolphus Raymond only pretends to be drunk. Outside the courthouse, Raymond explains that as a white man living with a black woman, most of Maycomb's citizens do not accept this lifestyle. So, he pretends to be drunk to give them a reason for his "odd" behavior. Scout asks why he would share this secret with them (Scout, Dill, and Jem). Raymond replies that children are open-minded enough to understand it. This implies that (most) adults are narrow-minded and intolerant, with some too stubbornly set in traditional ways of thinking.