Everyone wants to get something for nothing - whether it's a lucky upgrade that means you can turn left when you get on a plane instead or heading off into the economy seats, or even getting a few extra features thrown in for free when you buy a new car.

As some of the sharpest businesses around, no-one understands this quite as well as casinos and that's why they all have a system that they call comps. It's short for "complimentary offers" and these are special treats specially designed to reward you for your loyalty to the casino in question. They're basically bonuses.

A 1934 Packard Chassis Coachbuilt Body is displayed during The Quail, A Motorsports Gathering, in Carmel, California, U.S. August 19, 2016. The Pebble Beach Concours d'Elegance is an automotive charitable event held each year on the Pebble Beach Golf Links in Pebble Beach, California, considered the most prestigious event of its kind. It is the finale of Monterey Car Week held in August every year. (Photo by Michael Fiala/Reuters/Courtesy of The Revs Institute)

A 1949 Porsche 356 SL is displayed during the Porsche Rennsport Reunion V at Laguna Seca Raceway near Salinas, California, September 26, 2015. The three-day reunion is billed by organizers as the world's largest gathering of Porsche racecars, renowned drivers, and Porsche collector cars. (Photo by Michael Fiala/Reuters)

A photographer with a passion for wild animals was able to get up close and personal with one of nature’s deadliest creatures. Alex Suh has traveled to Mexico’s Banco Chinchorro reef twice in the past three years to get into the waters and capture the crocodiles in their natural habitat after an invitation from Yucatan Dive Trek. (Photo by Alex Suh/Caters News Agency)

“Wombats are Australian marsupials; they are short-legged, muscular quadrupeds, approximately 1 metre (39 in) in length with a short, stubby tail. They are adaptable in their habitat tolerances, and are found in forested, mountainous, and heathland areas of south-eastern Australia, including Tasmania, as well as an isolated patch of about 300 ha in Epping Forest National Park in central Queensland”. – Wikipedia

Photo: “Abdul”, a baby Common Wombat, is one of the marsupials on show during the spring baby boom at Taronga Zoo September 1, 2005 in Sydney, Australia. “Abdul” was orphaned when his mother was killed by a car. (Photo by Mark Nolan/Getty Images)

Emergency responders respond to the scene of a 565-foot-tall crane that toppled and flipped upside down, stretching along nearly two city blocks in downtown Manhattan in New York, February 5, 2016. The massive construction crane collapsed in lower Manhattan during a swirling snowstorm on Friday, killing one person and crushing a line of parked cars in the first accident of its kind in New York City since 2008. (Photo by Brendan McDermid/Reuters)

The “Hoegh Osaka” ro-ro cargo ship, operated by Hoegh Autoliners AS, sits grounded on Bramble Bank in the Solent near Cowes, on the Isle of Wight, U.K., on Monday, January 5, 2015. The car transporter was deliberately grounded after developing a list, shortly after it left the Port of Southampton. (Photo by Simon Dawson/Bloomberg)

A model poses beside the Porsche Hybrid during the media day of the Shanghai International Automobile Industry Exhibition at Shanghai New International Expo Center on April 19, 2011 in Shanghai, China. The 14th Shanghai International Automobile Industry Exhibition (Auto Shanghai 2011) will be held from April 21 to 28 with the theme of “Innovation For Tomorrow”. About 2,000 carmakers and parts providers from 20 countries are due to showcase 1,100 car models, 75 of which makes their world premieres in the auto show. (Photo by Feng Li/Getty Images)