Mike “The Bedfordshire Bull Botteley” (left) takes on Chris “The General” Levy during a Chessboxing bout at the Scala nightclub on March 10, 2012 in London, England. A new hybrid sport combining chess and boxing in alternate 3 minute rounds, the winner is the one who knocks out or checkmates their opponent first. (Photo by Matthew Lloyd/Getty Images)

An Indian Runner duck searches for food on a snow-covered meadow in Aitrang, southern Germany, Wednesday. April 19, 2017. (Photo by Karl-Josef Hildenbrand/DPA via AP Photo)

Kamaz Russian driver Eduard Nikolaev, co- driver Evgeny Yakovlev and mechanic Vladimir Rybakov compete during the 2018 Dakar Rally' s Stage 13 between San Juan and Cordoba in Argentina, on January 19, 2018. (Photo by Franck Fife/AFP Photo)

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 reveller performs while attending the block party “Galo da Madrugada” during carnival festivities in Sao Paulo, Brazil on February 25, 2020. (Photo by Rahel Patrasso/Reuters)

Burning effigies of winter during a celebration of Maslenitsa festival (Pancake Week) at the Etnomir (Ethnoworld) cultural and educational center in Kaluga Region, Russia on March 1, 2020. The holiday celebrates the end of winter and marks the arrival of spring. (Photo by Sergei Bobylev/TASS)

Determination: silver. Adam Pelech (No 3) of the New York Islanders and Brian Boyle of the Florida Panthers crash the boards during their game at Barclays Center in New York. (Photo by Al Bello/Getty Images)

A relative of murdered prisoner, lies on a chair next to his coffin during a wake after a prison riot in the city of Altamira, Para state, Brazil on July 30, 2019. At least 57 prisoners were killed by other inmates during clashes between organized crime groups in the Altamira prison in northern Brazil Monday with 16 of the victims being decapitated, according to prison officials. (Photo by Bruno Kelly/Reuters)