Between 1993 and 2007, as U.S. factories became highly automated, every new robot eliminated 5.6 human jobs, an economic think tank estimated in a study. Now automation is starting to eat into a new industry: food and hospitality. Workers are concerned -- according to the New York Times, the labor union that represents Marriott International hotel workers is demanding measures that will protect staff from being replaced by robots. The Times' take is that food and hospitality jobs have been spared by automation because service workers make so little. But cheap, effective artificial intelligence means those jobs are no longer secure.

The idea of putting robots to work in hotels started as a novelty, but is slowly gaining acceptance throughout the industry. A boutique hotel that opened this month near Los Angeles International Airport has already put two robots to work while a 288-room hotel in San Gabriel plans to employ eight robots when it opens in January. The latest automated additions come a year after a Santa Clara, Calif., company called Savioke put 12 robots in hotels across the country, including one named Wally at the Residence Inn by Marriott near LAX. So far, the tasks reserved for the water-cooler shaped automatons are simple: When guests call down to the front lobby for linen, luggage or food, the robots will be deployed to roll into an elevator and up to the room to make the deliveries. "Robots are the next wave of hospitality technology and we believe our overnight guests and those in the local San Gabriel community will find the robots to be intriguing and fun," said Wanda Chan, general manager of the Sheraton Los Angeles San Gabriel.