Casinos come in many sizes and shapes: Some float down the Mis- sissippi River, some are on stationary barges that never sail, some are in the middle of a moat, and some are on dry land. Most casino op- erations either have their own hotel or are supported by a hotel com- plex. Generally, the casino in a casino-hotel complex, not the hotel, is the. economic engine that drives the operation. Las Vegas has over 120,000 hotel rooms. Because the principal target population Las Ve- gas draws from is over 275 miles distant, gamblers need a place to stay. Atlantic City, on the other hand, has only 25,000 hotel rooms because its principal target market population lives within a two-hour drive. Consequently, most of its customer base is made up of people who are staying for just one day, or day-trippers. This has led to the growth of a previously untapped transportation format, the busing program.