same time.

Since the Ewell family has no lower stratum of society to which the members can drop among the citizenry of Maycomb, it is impossible to shame them. Also, since they have neither shame nor money, legal measures against them are virtually ineffective. For instance, since there is no parental insistence on an education, Burris and his siblings feel no need to attend school. "I done done my time for this year" (Ch.3), announces the unashamed Burris to Miss Caroline on the first day.

It would not profit the city to pursue the matter of Burris's truancy since the Ewells have no money with which to pay any fines. Placing Bob Ewell in jail would also accomplish little since he does not work, and he would lose nothing by being incarcerated for a while and being fed by the county. Because he hunts and provides some food for the children, the town authorities allow him to break the law and stay out of jail.

That Bob Ewell is incorrigible is exemplified in the fact that he is "fired from the WPA for laziness" (Ch. 27). Since little can be done with such a man as Bob Ewell, he is sometimes tolerated by disgruntled authorities.  

To Kill a Mockingbird by Harper Lee is set in Maycomb, Georgia, at a time when the divisions between races (blacks and whites and mixed) is pronounced and prolific; in this novel, the lines between certain types of people are equally pronounced.

Harper Lee does not stereotype all blacks as being one way and all whites another; in fact, the story is so effective, at least in part, because she does not do that. Instead of depicting all blacks as being deferential and kind, she gives us a rather unruly and rude black woman who has the nerve to show up at her own church and treat the visitors (who happen to be the white Finch children) with disrespect. In the same way, she does not characterize all poor, white people as being the same.

Early in the novel we meet the Cunninghams, a white family who is exceptionally poor but who pay their debts the best they can and act honorably when they know they should. We learn by watching Walter Cunningham interact with Atticus Finch that being poor does not mean anything more than not having money. The boy is polite and knowledgeable about things the Finch children are completely ignorant about, and his lack of education is only due to circumstances beyond his control.

The Ewells, on the other hand, are a poor, white family which is not as honorable and upstanding as the Cunninghams. Burris Ewell, for example, is a rude and unruly boy who shows up for school every year on the first day but who does not attend school after that. When Scout asks her father about it, he says:

 “Sometimes it’s better to bend the law a little in special cases. In your case, the law remains rigid. So to school you must go.”

He explains to Scout that the Ewells live in a way she can hardly imagine and therefore special measures need to be taken to makes sure the family is able to survive.

He said that the Ewells were members of an exclusive  society made up of Ewells. In certain circumstances the common folk judiciously allowed  them certain privileges by the simple method of becoming blind to some of the Ewells’ activities. They didn’t have to go to school, for one thing. Another thing, Mr. Bob Ewell, Burris’s father, was permitted to hunt and trap out of season.

This is because Ewell drinks up all the money he gets, and if he were not allowed to hunt, the children would get nothing to eat.

Scout is old enough and bright enough to know that this is not particularly fair or right; however, her father has a point:

“Mr. Ewell shouldn’t do that--”

 “Of course he shouldn’t, but he’ll never change his ways. Are you going to take out your disapproval on his children?”

The Ewells and the Cunninghams both represent the poorest of the poor families in this community, yet they are not the same. While the Cunninghams are principled and do the best they can with what they have, the Ewells, particularly Bob Ewell, are people who have to take in order to have anything. 

I will let one of Scout's classmates take a stab at answering your question first,

“He’s one of the Ewells, ma’am,” and I wondered if this explanation would be as unsuccessful as my attempt. But Miss Caroline seemed willing to listen. “Whole school’s full of ‘em. They come first day every year and then leave. The truant lady gets ’em here ‘cause she threatens ’em with the sheriff, but she’s give up tryin‘ to hold ’em. She reckons she’s carried out the law just gettin‘ their names on the roll and runnin’ ‘em here the first day. You’re supposed to mark ’em absent the rest of the year…”

Atticus later tells Scout that there is more to this story than what she thinks. Scout wants to quit school, knowing that she is smarter than Burris Ewell. Atticus takes time to explain to her what she needs for instructional and social development. However, the Ewell family does not have the same values. So, the government officials and the truancy officer uphold their duty to the law to get the kids into school, but the parent really has to make them go. This is obviously something they have struggled with regarding Bob Ewell. They are allowed special privileges because Mr. Ewell won't do anything about it and no one wants to fight with him. I don't really think we can call these special privileges, they are more like disadvantages.

The Ewells are the most despicable family in Maycomb County, and the head of their household, Bob Ewell, is the antagonist of the story. The Ewells live behind the Maycomb dump and have thrived on county welfare money for three generations. Bob Ewell is a notorious alcoholic, who is physically abusive to his daughter, Mayella. The county continually makes concessions for the Ewell family like allowing Bob to hunt out of season and disregarding their truancy issues. Scout mentions that no one knows for sure how many Ewell children there are but Mayella is responsible for raising her numerous siblings. Burris, Mayella, and Bob Ewell are all depicted as rude, conniving, morally debased individuals, who try to take advantage of others and have no regard for anyone but themselves.

The main function of the Ewell family is to drive the plot of the story by falsely accusing Tom Robinson of committing a serious crime. Bob Ewell accuses Tom of assaulting and raping his daughter, and Mayella attempts to corroborate his story. As a result of their false accusations, Atticus is forced to defend his black client in front of a prejudiced jury. During the trial, both the Ewells offer conflicting testimonies, and Atticus reveals that Bob was actually the perpetrator. Despite winning the case, Bob feels embarrassed and seeks revenge on Atticus and his family. In his attempt to get revenge, Bob Ewell attacks Jem and Scout while they are walking home alone from the Maycomb Halloween festival. Fortunately, Boo Radley intervenes and ends up killing Bob before he can seriously harm the children. Overall, the Ewells are the epitome of evil and are depicted as morally depraved throughout the story, and Bob is considered the novel's antagonist.