Uthen Kukheaw of Thailand in action during a Mixed Doubles Bronze match at the Teqball Tour in Qingdao, China on August 6, 2023. (Photo by Alex Plavevski/EPA/EFE)

A woman dressed in Qing dynasty style clothing rides a bicycle along a street near the Forbidden City in Beijing on October 24, 2023. (Photo by Wang Zhao/AFP Photo)

Photographer Will Evans captured this New Forest foal under an incredible double rainbow at Wilverley Inclosure near Brockenhurst, UK on September 21, 2023. (Photo by Will Evans/SnapPhotography/Bournemouth News)

Women wipe the sweat from their faces as they wait for bus on a hot and humid summer day in Mumbai, India, Thursday, May 23, 2024. (Photo by Rafiq Maqbool/AP Photo)

Farmer Zhang Xianping rides his pig "Big Precious" during an interview with the media, in Zhangjiakou, Hebei province, China, November 2, 2015. Zhang, a pig breeder, instead of killing it, decided to keep the two-year-old "Big Precious" as pet when its weight reached 600 kg, according to local media. (Photo by Reuters/China Daily)

An AH-64D Apache attack helicopter flies in front of a wall of fire during the South Carolina National Guard Air and Ground Expo at McEntire Joint National Guard Base, South Carolina, U.S. on May 6, 2017. (Photo by Jorge Intriago/Reuters/Courtesy Air National Guard)

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.

Competitors gather backstage as they prepare to take part in the All Ireland Irish Dancing Championships on November 2, 2016 in Belfast, Northern Ireland. The championships take place at the Waterfront Hall over the course of six days with winners qualifying for the World Irish Dancing Finals which will take place in Dublin next year. (Photo by Charles McQuillan/Getty Images)