The title "Good Country People" becomes ironic in Joy/Hulga's view of those around her and the events that occur within the story. Holding a PhD, Hulga views herself as superior to her mother and her neighbor. She regards their simple religious faith with condescension. They are blinded by their naivete, Hulga thinks, as she scoffs their spiritual beliefs. When a Bible salesman comes to the house, Hulga believes that he is like her mother, another representative of a "good country" person. She stereotypes this man as being simple, innocent, and unenlightened to the reality of the world. A nihilist herself, Hulga wants to show him the truth--that life is truly meaningless and absurd. She plans to seduce him, to rob him of his faith, and to make him see her way of viewing of the world.
Ironically, Hulga has grossly misjudged this young Bible salesman. Instead of being "good country people," he, like Hulga, believes in nothing as well. He is immoral. Instead of being seduced, he seduces Hulga, and robs her of her artificial leg and leaves her stranded in the hayloft. Hulga has definitely met her match, and has been outwitted and outmatched by a pretender, one who acts according to the very philosophy she professes. In this way, the title becomes highly ironic.