I'm not sure how much materialism is a theme in this story. The words and actions of the middle-aged waiter form the basic philosophical structure of “A Clean, Well Lighted Place,” but Hemingway sharply contrasts his beliefs with those of the other two characters, the young waiter and the old man. Unlike the middle-aged waiter, the young waiter is in a hurry; he has something to live for, namely, getting home to his wife. He has “everything,” “youth, confidence, and a job.” He seems to have everything going for him and retains his purpose in life; he does not seem to understand the depression that has overtaken his colleague, nor why his colleague is drawn to the “clean, well lighted” café. To that extent there is a sense of materialism and security the youth has.