In Chapter 2 of "To Kill a Mockingbird," as Scout attends her first day back in school, "Molasses buckets appeared from nowhere" at lunch time. The new teacher, Miss Caroline walks along the desks and stops at the desk of Walter Cunningham:
Walter Cunningham's face told everybody in the first grade he had hookworms. His absence of shoes told us how he got them. People caught hookworms going barefooted in barnyards and hog wallows. If Walter had owned any shoes he would have worn them the first day of school and then discarded them until mid-winter.
Later Atticus said,
professional people were poor because the farmer were poor. As Maycomb County was farm country, nickels and dimes were hard to come by for doctors and dentists and lawyers. Entailment was only a part of Mr.Cunningham's vexations. the acres not entailed were mortgaged to the hilt, and the little cash he made went to interest....As the Cunninghams had no money to pay a lawyer, they simply paid us with what they had....Dr. Reynolds works the same way....He charges some folks a bushel of potatoes for delivery of a baby.
Of course, the Ewells are also very poor. In Chapter 17 Scout describes how they live:
behind the town garbage dump in what was once a Negro cabin. The cabin's plank walls were supplemented with sheets of corrugated iron, its roof shingled with tin cans hammered flats, so only its general shpae suggested its original design...The varmints had a lean time of it, for the Ewells gave the dump a thorough gleaning every day, and the fruits of their industry..made the plot around the cabin look like the playhouse of an insane child....[with] scrawny ornage chickens pecking hopefully.
And, poor Tom Robinson has company in his poverty with many of the other black members of the town. When Scout and Jem attend church with Calpurnia, Scout asks Calpurnia why they do not have prayer books. During the service, a collection is taken up for Mrs. Robinson who cannot find work. In addition, in the chapters about the trial of Tom, there are indications of the poverty of some of the residents as they appear in the courtroom.
I've provided 4 quotes from my copy of this novel; all four quotes are from Scout's description of the poverty-stricken existence of Bob Ewell and his children. These descriptions were provided by Scout leading up to the trial. Bob Ewell mentions early in his testimony that his wife is dead.
"In Maycomb County, it was easy to tell when someone bathed regularly, as opposed to yearly lavations: Mr. Ewell had a scalded look; as if an overnight soaking had deprived him of protective layers of dirt. . . .Mayella looked as if she tried to keep clean. . ."
"Every town had families like the Ewells. . . .(they) lived as guests of the county in prosperity as well as in the depths of depression. . . .no public health officer could free them from congenital defects, various worms, and the diseases indigenous to filthy surroundings."
"Maycomb's Ewells lived behind the town garbage dump. . . .The cabin's plank walls were supplemented with sheets of corrugated iron, its roof shingled with tin cans hammered flat. . . ."
". . .the Ewells gave the dump a thorough gleaming every day, and the fruits of their industry (those that were not eaten) made the plot of ground around the cabin look like the playhouse of an insane child. . .a discarded dentist's chair, an ancient icebox. . .old shoes, worn-out table radios. . . ."