The setting is integral to the purpose of Bradbury's story. The futuristic setting of 2053 is one in which technology has created realities in which people no longer interact with the outside world as freely as they used to do. The pedestrian walks as freely as he does because the world around him has become inwardly drawn. The setting that Bradbury constructs is one in which people remain inside, watching televisions and using technology to avoid interacting with the outside world. This lack of external contact is what makes the pedestrian so different and the source of police interest. The pedestrian, who says, "Hello, in there" to the homes in which people are avidly watching television, walks alone in this world.
The setting is one in which the pedestrian's actions arouses police interest because he is breaking the norm, acting in an unconventional and thus, not controlled manner. The setting that is "empty, silent, and motionless" is reflective of a condition in which freedom is discouraged. It is one in which the pedestrian is a threat. This is where the setting assists in the development of the story's themes.