What does the escalator (mentioned in the prologue) symbolize in the book, Disoriental?

The author uses the escalator to highlight the contrast between Darius's values and the cultural values he associates with the citizens of Paris. Once the Sadr family has been exiled from Iran for their status as revolutionaries in opposition to the Shah, they must learn to adapt quickly to life in France. Darius has a specific view about escalators that sheds a great deal of light on the belief system he had brought with him to France and how it is in direct conflict with the elements of Paris that cause him to think of the French as materialistic, lazy, rich, and self-absorbed. Kimiâ says she remembers his determined and slightly disgusted expression as he charged up the stairs adjacent to any escalator they encountered, saying, "According to Darius Sadr's logic, that kind of luxury was a sort of abuse, if not outright theft" (12).