In the drama, "Death of A Salesman," Willy Loman arrives at home from a sales trip early. He does arrive at home at night, but he is earlier than expected. He arrives at night because he has traveled from another town, and wasn't having much luck. he came home from his out-of-town sales trip earlier than his family expected. He doesn't come home in the "middle of the night." If you remember during this first scene Charlie comes over and they even play cards awhile before Willy heads upstairs to bed. His family go up to bed earlier and he remains in the kitchen. During that period in American History it was not unusual for people to go to bed quite early because they got up very early. This may be why you thought it was the middle of the night.