Difference between how grandmother Henderson and margarite view the Poot white trash children in chapter 5 of i know why the bird sings

In Chapter 5, Maya explains that their grandmother is strict, requiring them to bathe even in the midst of winter. She urges them to correctly address adults. The poor white trash even demand respect as they order people around the store, and Willie and Momma obey. Maya recalls one day when she was sweeping patterns into the dirt in the yard. The young girls come and destroy the patterns. They mimic Momma and disrespect Maya. Momma just stands and takes it while singing. Eventually they leave, and Maya realizes Momma has won by standing up to them.