Model Bella Hadid walks the runway for the Savage X Fenty Fall/Winter 2018 fashion show during NYFW at the Brooklyn Navy Yard on September 12, 2018 in Brooklyn, NY. (Photo by Kevin Mazur/Getty Images for Savage X Fenty)

A supporter wears a mask of US President Donald Trump on August 17, 2020 in Mankato, Minnesota as the president delivers remarks on jobs and the economy. (Photo by Kerem Yucel/AFP Photo)

Metropolitan Police run as they escort people, some without shoes, away from a shooting scene in the northwest part of the city on April 22, 2022 in Washington, DC. Police evacuated residents from the shooting scene Friday afternoon and there were reports of several shooting victims. (Photo by Kevin Dietsch/Getty Images)

Jordan Spence and Dawson Stallworth watch waves come ashore as Hurricane Sally approaches in Orange Beach, Alabama, U.S., September 15, 2020. (Photo by Jonathan Bachman/Reuters)

US Army Parachute Team Golden Knights perform a precision drop to commemorate the 50th anniversary of the end of the Vietnam War, above West Potomac Park in Washington, DC, USA, 11 May 2023. The performance is one of many activites being held on the National Mall over three days to honor Vietnam War veterans and their families and to commemorate the 50th anniversary of when the last US combat troops left South Vietnam in 1973. (Photo by Michael Reynolds/EPA/EFE)

Girls sits on a bench during summer at the Central Park in New York, United States, 2011. (Photo by An Rong Xu)

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.

An Extinction Rebellion protestor holds up a sign saying “You Can Change Climate Change” in St Martin's Lane in London, United Kingdom on August 23, 2021. (Photo by James Veysey/Rex Features/Shutterstock)