Charli XCX performs on day three of the Pitchfork Music Festival at Union Park on July 21, 2019 in Chicago, Illinois. (Photo by Michael Hickey/Getty Images)

A handout picture provided by Global newsroom of Czech Martin Sonka (C) leading Nigel Lamb (top) of Great Britain and Yoshihide Muroya of Japan (down) along the Mount Fuji prior the third stage of the Red Bull Air Race World Championship in Chiba, Japan on June 1, 2016. (Photo by Predrag Vockovic/EPA/Global Newsroom)

Workers from the South Florida Science Center and Aquarium and Imagine Exhibitions put together an animatronic spinosaurus outside the science center in West Palm Beach, Fla., Tuesday, October 27, 2015. The giant spinosaurus is part of the Dinosaurs Around the World exhibit, set to open on November 1. (Photo by Maria Lorenzino/South Florida Sun-Sentinel via AP Photo)

An armed man herds his cattle close to the village of Nimini in northern South Sudan, February 8, 2017. In the chaos of South Sudan's civil war, it took three years for Nyagonga Machul to find her lost children. Machul had traveled from her village to the capital when President Salva Kiir, an ethnic Dinka, fired his deputy Riek Machar, a Nuer, in 2013. (Photo by Siegfried Modola/Reuters)

Cambodia's Kun Sreynich and Philippines' Lopez Leah in action during individual judo finals at Chroy Changvar Convention Centre Hall C in Phnom Penh, Cambodia on May 15, 2023. (Photo by Kim Kyung-Hoon/Reuters)

Beach volleyball athletes from Lithuania and Spain train in Paris on July 25, 2024. (Photo by Louisa Gouliamaki/Reuters)

Andrea Spendolini Sirieix and Lois Toulson of Britain in action during the women's synchronized 10m diving at the Paris Olympics on July 31, 2024. (Photo by Leah Millis/Reuters)

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.