I would want to answer this question by looking at the inconsistencies of Abner Snopes in terms of his words and actions. Firstly, it is highly paradoxical that Abner Snopes lectures his son, Sarty, about the importance of family bonds whilst at the same time beating him for the way he perceived that Sarty would have testified against him. Note how this section of the text is presented:
"You were fixing to tell them. You would have told him." He didn't answer. His father struck him with the flat of his hand on the side of the head, hard but without heat, exactly as he had struck the two mules at the store, exactly as he would strike either of them with any stick in order to kill a horse fly, his voice still without heat or anger: "You're getting to be a man. You got to learn. You got to learn to stick to your own blood or you ain't going to have any blood to stick to you."
Abner beats his son like he would his mules, and whilst we can appreciate the sentiment behind his advice to "stick to your own blood," at the same time the way he encourages his son to do so indicates that Abner himself is a pathetically violent man who only gives his son extra reason to not "stick to his own blood" through his actions and treatment of him.
Secondly, I would want to talk about the actions of Abner and how he responds to his situation. Although he clearly resents being beholden to those who are socially superior to him, Abner never tries to escape the cycle of land-tenancy that he subjects his family and himself to. At each stage he seems to deliberately annoy or slight his employers, bringing down trouble upon himself, to give him a reason or a "justification" for barn burning. He seems to deliberately provoke conflict so that he can engage in his acts of arson. He seems to have condemned himself to his own personal hell and desires to do nothing to escape it. It is Sarty's realisation of this that forces him to leave his father's tyranny.