People participate in the Winter Snow Sports Festival in Kalam, about 99 km from Mingora in the northern upper reaches of Swat valley on February 12, 2022. (Photo by Abdul Majeed/AFP Photo)

Models present creations by LaQuan Smith at the Intrepid during fashion week in Manhattan, New York City, U.S., September 12, 2022. (Photo by Caitlin Ochs/Reuters)

A girl holds her hedgehog to be blessed by a priest at the Cathedral San Bernardino de Siena during the ceremony commemorating the Feast of San Antonio Abad, the patron saint of domestic animals, in Xochimilco on the outskirts of Mexico City, Mexico on January 17, 2024. (Photo by Raquel Cunha/Reuters)

A woman clutches a teddy bear covered in red paint to symbolize blood during a government-approved, anti-violence rally held in the Kazakh city of Almaty on November 26, 2023. Organized by the New People youth movement, roughly 300 people took part. The rally was dubbed “Say No To The Animal World”, with organizers likening violent people to animals. (Photo by Petr Trotsenko/Radio Free Europe/Radio Liberty)

Flamengo soccer fans cheer a goal scored by Gabriel against Argentina's River Plate in the Copa Libertadores final match, broadcast on a giant screen at a watch party at the Macarena Stadium, in Rio de Janeiro, Brazil, Saturday, November 23, 2019. The first single-match final will be played in front of more than 65,000 fans at Lima’s Monumental Stadium. The match was originally scheduled for Santiago’s National Stadium, but it was moved because of street protests in Chile. (Photo by Silvia Izquierdo/AP Photo)

United States's Jessie Diggins celebrates winning the cross-country ski, women's Tour de Ski overall standings, in Val di Fiemme, Italy, Sunday, January 7, 2024. (Photo by Alessandro Trovati/AP 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.

Military officers look at an AR-10 sniper rifle at LAAD, the biggest military industry expo in Latin America in Sao Paulo, Brazil April 10, 2018. (Photo by Nacho Doce/Reuters)