How Las Vegas Casinos Make Money

The House Odds
Every casino sets the odds of winning for most of its games. (The odds are the chances of a winner coming out based on a certain number of times the game is played.) In order to make money, the casino simply has to tweak the odds slightly in its favor. This isn't hard to do for slot machines, roulette wheels and the like, and the house charges a modest fee for games like poker that may not involve them directly. The odds vary from game to game, and they don't have to favor the house by much. Just a few percentage points---applied over time and to every gambler who sets foot in a Vegas casino---translates to far more money than a casino loses to the odd jackpot or lucky streak.
Try looking for a clock in a La Vegas casino sometime or getting to an exit from the center of the floor. While European casinos are often designed around aristocratic salons, Vegas casinos resemble labyrinthine mazes, luring gamblers in and refusing to let them out. A gambler can spend hours at the tables without any knowledge of the passage of time. He can wander slowly from one slot machine to the next without ever finding his way outside. The longer people gamble, the more money the house odds grind out and the greater the profit the casino makes.
Human Nature
Everyone loves stories like "Ocean's Eleven" where a clever man with a slick plan beats the house at its own game. In truth, many of Las Vegas's gamblers simply don't know how to play the game very well. Others do it more for the enjoyment of playing rather than any set desire to win. Amateurs vastly outnumber the professional gamblers with the patience and skill to turn a profit. Las Vegas's casinos augment this by offering attractions other than gambling--concerts, magic shows and even free displays like the dancing fountains at Bellagio or the pirate ship at Treasure Island--to bring in people who don't know much about gambling but are happy to try it while on vacation. Free alcohol to people playing the games helps blunts players' perceptions and makes them more likely to take stupid risks. Such tactics enhance basic human nature to the point where the players who know what they're doing still can't make a dent in the casino's profits.