Team Japan competes during the team free preliminaries of artistic swimming at the 19th FINA World Championships in Budapest, Hungary, Wednesday, June 22, 2022. (Photo by Anna Szilagyi/AP Photo)

A man walks past a mural along a street in New Delhi on June 30, 2023. (Photo by Arun Sankar/AFP Photo)

Alex Jones races in the second set of heats during the “T-Rex World Championship Races” at Emerald Downs, Sunday, August 20, 2023, in Auburn, Wash. (Photo by Lindsey Wasson/AP Photo)

On the July 10, 2025, an elderly couple in Eonam-dong, Jung-gu, Daejeon, who finished their field work, cooled off by sitting on a bench in the yard near the water tap. (Photo by Shin Hyeon-jong)

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 elephant sprays tourists with water in celebration of the Songkran Water Festival in Ayutthaya province, north of Bangkok, Thailand April 11, 2017. Trained elephants sprayed motorists and passers-by with water in Thailand's old capital city of Ayutthaya on Tuesday to welcome in the Buddhist New Year, known as “Songkran”. (Photo by Chaiwat Subprasom/Reuters)

Performers are seen as a 90-year old spruce tree cut down in the woods of the Shchyolkovsky District in Moscow Region, Russia on December 16, 2021 is sent to Moscow. The almost 28-metre high tree will be put up at the Moscow Kremlin's Sobornaya (Cathedral) Square this New Year and Christmas. (Photo by Vasily Fedosenko/TASS)

Volunteers of a Wild Nature Preservation center release a group of owl chicks from the Toro Mountain in Menorca, Balearic Islands, Spain, 31 July 2019. (Photo by David Arquimbau Sintes/EPA/EFE/Rex Features/Shutterstock)