After their recent trip to the Theatre Guild, Ma and Pa were on their way home. Pa was relieved to have survived this involuntary infusion of culture and suggested they stop at his country club (otherwise known as "Mort's Diner") for lunch.
Unfortunately, Ma leaves her glasses on the table, but doesn't miss them until they were back on the highway. By then, they had to travel quite a distance before they could find a place to turn around.
Pa naturally fusses and complains all the way back to Mort's.
When they finally arrive, as Ma is leaving the car to retrieve her glasses, Pa remarks,
"While you're in there, you may as well get my hat, too."