Answer:
Scott assumed that Miss Caroline will automatically understand that Walter will not accept her offer of money to buy lunch.
The residents of Maycomb automatically associate "the Cunningham tribe" as a family with a sense of pride in their own capabilities.
Explanation:
In Chapter 2 of Harper Lee's "To Kill A Mockingbird", the scene is in the school's classroom. Miss Caroline had offered a quarter to Walter Cunningham who had not brought any lunch. So, when Scott told her that he's a "Cunningham", she assumed that she will immediately understand the fact that the "Cunningham tribe" are a family with a strong sense of pride in their own abilities.
The residents of the town had already associated them with that label. So, it is understood by them that if anyone is a "Cunningham", then there is no possibility of that person taking or accepting any charity. Even though they are poor, the Cunningham have been shown as not accepting any form of free things. Mr. Cunningham had always paid back Atticus if any help was rendered to him. If he can't pay back with money, he'd still pay back with goods like nuts and vegetables. Never would he take any charity or free help from others.
