Scout learns to treat everyone like company from Walter’s visit.
Scout learns several things from Walter Cunningham’s visit. She learns that not everyone is like the Finches, for one thing. She is shocked and impressed with Walter’s dinnertime conversation, because he and Atticus talk to each other like adults.
While Walter piled food on his plate, he and Atticus talked together like two men, to the wonderment of Jem and me. (Ch. 3)
The most enlightening moment comes when Walter asks for syrup though. Why he asks for syrup we do not know. There is nothing in the meal that Scout thinks calls for syrup, and Walter pours it all over his plate. Scout asks him what in “sam hill” he is doing, and Walter stops and looks down at his lap, embarrassed. Atticus shakes his head at her to try to quietly warn her off, but Scout goes on to comment on the fact that he has poured so much syrup all over his plate.
Calpurnia calls Scout into the kitchen and explains that Scout needs to treat Walter more politely, because he is her company. She objects that he isn’t company because he is a Cunningham, and Cal gives her a lesson in manners and social class.
Don't matter who they are, anybody sets foot in this house's yo' comp'ny, and don't you let me catch you remarkin' on their ways like you was so high and mighty! (Ch. 3)
Cal’s point is that regardless of whether or not Walter Cunningham is poor, Scout invited him into her house, and he needs to be treated politely and with respect. She should let him do whatever he wants, more or less, or at least not call attention to his habits, because it is impolite.
Scout got a lesson in social class and manners here. Walter acts different because he is of a different class than Scout. However, she cannot treat him rudely, according to both her father and her housekeeper. Atticus has different feelings about class than some of the others in Maycomb. You can tell by how he treats Walter, and how he wants Scout to treat him. Everyone deserves respect, especially when that person is a guest in your house.