A woman walks between Christmas trees at a Christmas market opened prior to incoming Christmas and New Year festivities in St. Petersburg, Russia, Friday, December 15, 2023. (Photo by Dmitri Lovetsky/AP Photo)

People move on a tractor through a flooded street amid severe flooding in Feni, Bangladesh, on August 25, 2024. (Photo by Mohammad Ponir Hossain/Reuters)

A chimpanzee relaxes in the shade at the Safari Park as the popular attraction prepares for the upcoming Jewish festival of Pesach (Passover) on April 14, 2008 in Ramat Gan near Tel Aviv, Israel. (Photo by David Silverman/Getty Images)

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.

The Arizona State Sun Devils cheer team performs during the second half of the NCAAF game at Sun Devil Stadium on September 01, 2022 in Tempe, Arizona. (Photo by Christian Petersen/Getty Images)

France's defender #07 Sakina Karchaoui (L) and France's forward #11 Kadidiatou Diani (R) celebrate their win at the end of the Australia and New Zealand 2023 Women's World Cup Group F football match between France and Brazil at Brisbane Stadium in Brisbane on July 29, 2023. (Photo by Dan Peled/Reuters)

Paris Saint-Germain's Italian goalkeeper #01 Gianluigi Donnarumma and Salzburg's Serbian forward #21 Petar Ratkov vie for the ball during the UEFA Champions League football match between FC RB Salzburg and Paris Saint-Germain in Salzburg, Austria on December 10, 2024. (Photo by Franck Fife/AFP Photo)

Union Berlin players celebrate after the Bundesliga playoff second leg match between 1. FC Union Berlin and VfB Stuttgart at Stadion an der alten Foersterei on May 27, 2019 in Berlin, Germany. (Photo by Annegret Hilse/Reuters)