Sammy is nineteen years old and is in the space in life where he is no longer a child and not yet an adult. Legally, yes, he is an adult but he still answers to his parents.
Lengel mentions his as Sammy quits, “Sammy, you don’t want to do this to your Mom and Dad”(Updike 165). As Sammy comes closer to adulthood, he has to face the consequences of his actions more directly. Sammy is a couple years older than the girls who walk into A&P in their bathing suits. Sammy is similar to the girls because of their young age, but unlike the girls, Sammy can not use his parents to excuse his actions like the girls do when Lengel confronts them. Queenie used her parents by saying they had sent her to the store to buy some “herring snacks”(Updike 163).
Sammy will just have to answer to his parents’ disappointment and find another source of making money when he quits, and the dejected sense of foreboding he has at the end of the story carries the weight of the consequences he’ll have to face for his actions. Sammy’s rash act of quitting is a youthful act, inspired by his connection with the girls, but as he faces the consequences of his actions, he realizes that he’s no longer a youth as the girls are and will have to answer to the consequences as an adult.