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.

“It’s the end of the world, baby!” screams the title of the new 2012 calendar from Campari. Sensing the Mayan calendar’s apocalyptic spirit, Campari created a protagonist in supermodel Milla Jovovich to storm through the end of the world holding glasses and bottles of the red aperitif, all while dressed in impeccable couture. (Photo by Dimitri Daniloff/Campari)

People celebrate on a street in the neighborhood of Born, as the state of emergency decreed by the Spanish Government to prevent the spread of the coronavirus disease (COVID-19) gets lifted in Barcelona, Spain, May 9, 2021. (Photo by Nacho Doce/Reuters)

An undated handout photo obtained on May 14, 2022, from Khartoum's Marshall Nature Reserve for exotic birds, shows a visitor posing for pictures with some of the protected birds in the capital Khartoum. Tucked away east of Sudan's capital Khartoum, a sanctuary of lush green vegetation has been a haven for dozens of exotic birds from far and wide. (Photo by Khartoum Marshall Nature Reserve/AFP Photo)

A tattoo showing the Olympic rings is pictured on the leg of Mexico's Joana Jimenez Garcia during the Women Solo Technical Preliminaries, at the FINA World Championships, in Budapest, Hungary on June 17, 2022. (Photo by Marton Monus/Reuters)

United States Air Force Academy graduates cheer as the United States Air Force Thunderbirds fly over the graduation for the Class of 2021 at Falcon Stadium on May 26, 2021 in Colorado Springs, Colorado. Chairman of the Joint Chiefs of Staff General Mark A. Milley gave the commencement address to the 1,019 graduates from the academy. (Photo by Michael Ciaglo/Getty Images)

Nefertara, a supporter of pop star Britney Spears, wears an outfit inspired by the singer as she holds a picture of Britney that she painted, during a gathering on the day of a conservatorship case hearing at Stanley Mosk Courthouse in Los Angeles, California, U.S., September 29, 2021. (Photo by Mario Anzuoni/Reuters)

Shortlisted: The Life: A narrow strip, Río Tinto, Huelva, Spain. A narrow strip of road divides ochre-coloured and fresh waters. Trees wait on the fresh side of the road opposite the toxic waters of a nearby mine reservoir. (Photo by Roberto Bueno/CIWEM Environmental Photographer of the Year 2021)