People slide down a 1,082 feet (330 metre) long inflatable water slide in Hong Kong, China August 22, 2015. (Photo by Tyrone Siu/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.

Daniel J. Wabsey, a 58-year-old war veteran, sits outside his tent at Camp Hope in Las Cruces, New Mexico October 6, 2015. “I've been traveling for 35 or 38 years. Getting inside would take a while to get used to. I just want to be able to eat, sleep and be safe. We all get along and understand in Camp Hope. We've all been there. With common sense you can survive out here”, Wabsey said. Camp Hope describe themselves as an “alternative transitional living project for the homeless”. Around 50 people live at the camp. (Photo by Shannon Stapleton/Reuters)

Cosplayer Monzerath Gutierrez, who portrays Dragon Ball Z character Trunks, female version, poses for a portrait during the 4th edition of the MiniCon Anime convention, at the School of Dance, in Managua, Nicaragua, Sunday, July, 26, 2015. (Photo by Esteban Felix/AP Photo)

A bronze statue of late singer Ella Fitzgerald is seen wearing a hat and protective face mask, as the global outbreak of the coronavirus disease (COVID-19) continues, outside the Metro-North Railroad Station Plaza in Yonkers, New York, U.S., November 17, 2020. (Photo by Shannon Stapleton/Reuters)

A worker assembles a sеx doll at the WMDOLL factory in Zhongshan, Guangdong Province, China, July 11, 2018. The factory has over 200 full-time workers, all dolls are handmade and each requires the cooperation of at least five workers. (Photo by Aly Song/Reuters)

People work to rescue a dog from under rubble, in the aftermath of a deadly earthquake, in Iskenderun, Turkey February 8, 2023, in this screengrab obtained from a social media video. (Photo by Gurcan Ozturk via Reuters)

Two female revelers engage in a beer drinking contest in the Hacker Pschorr tent on the first day of the 2017 Oktoberfest beer fest on September 16, 2017 in Munich, Germany. Oktoberfest is the world's largest beer celebration and typically draws over six million visitors over its three-week run. Oktoberfest includes massive beer tents, each run by a different Bavarian brewer, as well as amusement rides and activities. (Photo by Philipp Guelland/Getty Images)