Possible Clues:

• Vegas spread?
• Unrestricted city expansion ... and what begins in the circled letters (and ends in uncircled ones for you to find)
• Continuous network of towns — plans rub raw (anag)
• Uncontrolled growth around a city
• Growing problem in cities?
• Phenomenon facilitated by freeways
• Patriot's demography topic
• Uncontrolled city growth
• City's widespread development
• Uncontrolled town development