The novel would have less impact if poverty were not an issue. In fact, it is seemingly impossible for it to be a likely depiction of a southern small town in the 1930s without addressing issues of economics and race. Also, the issues of race were inextricably linked to issues of economics and poverty.
The title of the book comes from one of Atticus' lessons to the children. Miss Maudie elaborates on this in Chapter 10:
Mockingbirds don’t do one thing but make music for us to enjoy. They don’t eat up people’s gardens, don’t nest in corncribs, they don’t do one thing but sing their hearts out for us. That’s why it’s a sin to kill a mockingbird.
A mockingbird is something that does not harm anyone; in fact, the only thing the mockingbird does is sing, therefore giving a small but meaningful gift with no expectation of a thank you. The mockingbird is a symbol for people who do nothing wrong and sometimes do good deeds simply because it is the right thing to do. Like a mockingbird's song, poor people can not give much, but they do what they can. Take Walter Cunningham Sr. for example. He can not pay Atticus for his legal services so he gives him what he can: stovewood, hickory nuts, smilax and holly. Atticus teaches that it would be wrong not to help Walter simply because he can't pay in money. Aside from taking part in the mob when Tom is in the town jail, Walter keeps to himself and never intends to harm anyone.
But the two major characters that embody the definition of a mockingbird are Boo Radley and Tom Robinson. Both men do nothing wrong to anyone and they provide help to others. Boo saves the children in the end and Tom helps Mayella even though she turns on him.
The mockingbird symbol also applies more generally to the poor. Atticus helps Walter even though he can not pay; a similar sentiment that it would be a sin to kill a mockingbird. Tom is poor and this has a lot to do with the fact that African-Americans were discriminated against and therefore had less opportunities for high paying jobs and higher education. Atticus takes on his case because he knows he is Tom's only chance, small chance that it is. There is certainly a presence of racism among many of Maycomb's citizens but there is also a comparable condescension towards the poor. Only the good-hearted characters like Atticus refuse to be condescending in this way.
The Ewell family are quite poor as well. And while it may be difficult to sympathize with them, this is exactly what Atticus does, namely to help the children. In Chapter 23, when we learn that Bob Ewell has spit on Atticus, he explains why he didn't retaliate:
So if spitting in my face and threatening me saved Mayella Ewell one extra beating, that’s something I’ll gladly take. He had to take it out on somebody and I’d rather it be me than that houseful of children out there. You understand?
In this respect, even Mayella (and her siblings) fit the definition of a mockingbird. We might even say that when she asked Tom for help, she was reaching out, singing for help as it were. Atticus recognizes that it is not Mayella's fault being born into a poor family to a father who does nothing to help raise the children so that they might have a better future.
Poverty is inextricably linked to the predicament of the Cunninghams, the Ewells, and Tom and his family. Bob Ewell does not fit the definition of a mockingbird. But in certain contexts, many of the poorer characters do. If you take poverty out of the novel, it becomes all about race and the fact is that the novel and reality are not that simple.
"In the name To Kill a Mockingbird, how do we see the effects of poverty?" Does this question not ask how the title correlates to the motif of poverty?
If so, then, another story may provide clues to the answer. In "The Sky is Gray" by Ernest Gaines, the narrator, a young black boy, lives in the rural South in the 1930's without a father experiences poverty along with his mother, aunt, sister, and brother. Because he suffers from a terrible toothache, James's mother and he walk to the dentist in town; as they walk, the boy sees some birds called pool-doos and he wonders if people can eat these pool-dos because, he relates, he has not eaten this variety.
But I done ate owls and blackbirds, and I done ate redbirds, too. I didn't want to kill the redbirds, but she [his mother] made me kill them.....'cause we needed food.
Since Harper Lee's narrative is also set in the rural South of the Great Depression era, it, therefore, seems reasonable to suggest that this title does, indeed, connote poverty as well as symbolize the harm done to innocent people.
In the novel To Kill a Mockingbird by Harper Lee, there is a lot of poverty that is shown. The story takes in the south during the Great Depression. Even the Finches, who are higher in social class, aren't filthy rich. Since this is a southern town, the depression did hit hard on them. There is evidence among the Ewells and the Cunningham's. The Ewells are dirt poor, and they barely survive. The great depression hit them really hard since they have no money. Also, another family, the Cunningham's are poor as well. So poor, that the father, Walter Cunningham, pays back people not in money since he does not have money to give back.