Models prepare backstage before a creation from the Saint Joy by Bian Huizhong during the China Fashion Week in Beijing on March 30, 2023. (Photo by Wang Zhao/AFP Photo)

Rescuers attend an injured fan lying on the field of the Cuscatlan stadium in San Salvador, El Salvador, Saturday, May 20, 2023. At least nine people were killed and dozens more injured when stampeding fans pushed through one of the access gates at a quarterfinal Salvadoran league soccer match between Alianza and FAS. (Photo by Milton Flores/AP Photo)

A plane drops water to put out the fire broke out yesterday in a grassy area in Kizilcahamam district of Ankara and spread to a forest area in Gerede district of Bolu as firefighters, Turkish General Directorate of Forestry teams and officers continue their extinguishing and cooling efforts in the forest fire that is under control on August 22, 2024 in Bolu, Turkiye. (Photo by Emin Sansar/Anadolu via Getty Images)

Protesters throw fireworks at riot police during clashes in Nanterre, near Paris, France, 29 June 2023. Violence broke out after police fatally shot a 17-year-old during a traffic stop in Nanterre on 27 June 2023. According to the French interior minister, 31 people were arrested with 2,000 officers being deployed to prevent further violence. (Photo by Yoan Valat/EPA/EFE/Rex Features/Shutterstock)

Dressed in the colors of the Ukrainian flag, Maria Berdieva poses for photos to help raise money for Ukrainian troops in Kyiv, Ukraine, Monday, July 10, 2023. (Photo by Jae C. Hong/AP Photo)

Several beaches along South Florida's Atlantic coast line were closed after thousands of sharks were seen migrating in the waters. The sharks were migrating from Boca Raton to Jupiter since the beginning of March, marine biologists told NBC Miami. Photo: A spinner shark swims just offshore on Midtown Beach in Palm Beach on Tuesday. (Photo by Jeffrey Langlois/Palm Beach Daily News)

Armed Syrian Turkmen villagers are seen near the northern Syrian village of Yamadi, near the Turkish-Syrian border, Syria, November 24, 2015. Turkey shot down a Russian warplane near the Syrian border on Tuesday saying it had repeatedly violated its air space, one of the most serious publicly acknowledged clashes between a NATO member country and Russia for half a century. (Photo by Reuters/Stringer)

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.