I&#x27;m not certain about the illegal part, but plenty of urban development is very unpleasant to walk in. A lot of suburbs and a lot of city centers ravaged by urban renewal are plain repulsive, and even dangerous due to all the high speed traffic, to walk around in. It&#x27;s easy to say for a doctor to &quot;go walk outside&quot;, but not everybody can exit their front door in an area that&#x27;s welcoming to walking or cycling.