Aegean airlines air hostesses take selfies after a news conference in Athens, Wednesday, March 28, 2018. In a deal worth up to $5 billion, Greek airline Aegean says it will buy 30 new Airbus aircraft, with the option of an additional 12, to upgrade its fleet as the country expects to break tourism records. The signing of the final purchase agreement is expected in June. (Photo by Petros Giannakouris/AP Photo)

North Korean people line up on the street side and welcome the motorcade of Russian President Vladimir Putin and North Korean leader Kim Jong Un during their meeting in Pyongyang, North Korea, 19 June 2024. The Russian president is on a state visit to North Korea from 18-19 June at the invitation of the North Korean leader. He last visited North Korea in 2000, shortly after his first inauguration as president. (Photo by Gavriil Grigorov/EPA/EFE)

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.

Kaz Crossley and Laura Anderson seen attending ITV Palooza! at Royal Festival Hall on October 16, 2018 in London, England. (Photo by Splash News and Pictures)

A girl plays kayagum, stringed Korean harp, at the Tongmun kindergarten No.1 in Taedonggang District of Pyongyang, North Korea Tuesday, May 16, 2023. (Photo by Cha Song Ho/AP Photo)

A man wearing an illuminated atmospheric diving suit as part of an installation titled “What Lies Beneath” looks at members of the public during the Vivid Sydney festival of light and sound in Sydney, Australia, May 26, 2017. (Photo by Steven Saphore/Reuters)

Rita Ora leaving her hotel to go to BBC Children in need on November 07, 2018 in London, England. (Photo by Mark R. Milan/GC Images)

Some 1200 windsurfers take the start of the 21th edition of the Defi Wind in the Mediterranean Sea, off the coast of Gruissan in southern France, on May 19, 2023. (Photo by Charly Triballeau/AFP Photo)