In pre-automobile America, people lived in dense neighborhoods that provided for most of their everyday needs. Things like grocery stores, tailors, and the likes were located within a close walking distance to their homes. The density of cities and towns began to change with the development of new technology like the street car. People began to live in primarily residential neighborhoods, instead of places with a mix of uses. According to Richard Dover, Knoxville based supporter of infill development, the automobile allowed people to live further from commercial centers. This meant developers could build new, primarily residential communities away from the stores in areas known as green fields, which led to the creation of suburbs. Instead of putting new houses and businesses in cities and towns where there might be empty parcels, underused buildings, or buildings needing rehabilitation, developers looked outside these areas.