American singer Melissa Viviane Jefferson, known professionally as Lizzo performs at O2 Academy Brixton on November 06, 2019 in London, England. (Photo by Chiaki Nozu/WireImage)

The UK Love Island star Tasha Ghouri stunned in a white see-through dress in the second decade of August 2023. Tasha celebrated her birthday in style. (Photo by Instagram)

Tony Appleton, a town crier, announces the royal birth outside the Lindo Wing of St Mary's Hospital after Catherine, Duchess of Cambridge gave birth to a baby boy in central London July 22, 2013. Prince William's wife Kate gave birth on Monday to a baby boy, in the Lindo Wing of St Mary's Hospital, who becomes third in line to the British throne, his office said. The royal baby, the couple's first child, was born at 4:24 p.m. (15:24 GMT), weighing 8 lbs and 6 oz. (Photo by Lefteris Pitarakis/Associated Press)

A labourer carries a basket of bananas inside a wholesale fruit and vegetable market in Bengaluru, India, August 22, 2016. (Photo by Abhishek N. Chinnappa/Reuters)

A cow moves past a burning car that, according to fire officials, caught fire by an electrical short circuit after it was stuck in a water-logged road following heavy rains in Ahmedabad, India, July 11, 2022. (Photo by Amit Dave/Reuters)

June 21: “World War Z”. Brad Pitt battles zombie apocalypse in $170 million film by “Quantum of Solace” director Marc Forster. This publicity photo released by Paramount Pictures shows, center, Brad Pitt as Gerald Lane in a scene from the film, “World War Z”, from Paramount Pictures and Skydance Productions in association with Hemisphere Media Capital and GK Films. (Photo by Jaap Buitendijk/AP Photo/Paramount Pictures)

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.