Bahamas' Shaunae Miller-Uibo celebrates winning the women's 200 meters final at the Diamond League Birmingham Grand Prix in Birmingham, Britain on August 18, 2019. (Photo by Jason Cairnduff/Action Images via Reuters)

Pablo Holcer tests out a VR system made by Neurable that allows the user to control with their thoughts as the EEG headset interprets thoughts into actions in the VR environment at SIGGRAPH 2017 in Los Angeles, California, July 31, 2017. (Photo by Mike Blake/Reuters)

Nana Takano and Kaito Toyoshima, winners of the Shanghai preliminary and Asian Championship, compete in the final of the World Tango Championship final in Buenos Aires, Argentina, 27 August 2024. (Photo by Juan Ignacio Roncoroni/EPA)

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.

Two stallions confront each other at a horse fighting contest in Rongshui, China. More than 30 horses from surrounding regions took part in the traditional activity of the Lantern festival. (Photo by China Foto Press)

Nadezhda Sergeeva, of the Russian Olympic Committee, looks at her time in the women's monobob heat 4 at the 2022 Winter Olympics, Monday, February 14, 2022, in the Yanqing district of Beijing. (Photo by Pavel Golovkin/AP Photo)

A woman takes a picture of a sculpture depicting servant Puck from Shakespeare's comedy “A Midsummer Night's Dream” during a flower festival in Pakruojis, Lithuania on August 14, 2021. (Photo by Ints Kalnins/Reuters)