A little girl takes a picture of a lion in the zoo in Frankfurt, Germany, Tuesday, September 13, 2016. (Photo by Michael Probst/AP Photo)

The Sun rises above the forest near Kiskorpad, Hungary, 02 January 2021. (Photo by Gyorgy Varga/EPA/EFE)

Ciara is the latest victim to be pranked by Vitalii Sediuk outside the Valentino Fashion Show today during Paris Fashion Week on September 30, 2014. The singer looked chic in a red lace outfit with a black coat hanging over her shoulders and was all smiles while posing for pictures. However, the fun was ruined when Vitalii threw off his cape to reveal a Chanel top and speedos with a message on his right thigh, reading “Ban in USA but I Rock Chanel”. No big altercation went down but Ciara’s security removed him from the crowd. (Photo by Backgrid USA)

Sheep stand on a dyke as clouds cover the sky over Tossens, northern Germany, on September 2, 2019. (Photo by Mohssen Assanimoghaddam/dpa/AFP Photo)

This picture taken on January 25, 2015 shows a participant taking part in an ice water challenge in Zhangjiajie, central China's Hunan province. Participants were required to stay in an ice pond, holding an ice block while eating ice-cream with an electric fan blowing at them. (Photo by AFP Photo/Stringer)

Apple CEO Tim Cook discusses the new iPhone 6 and iPhone 6 plus on Tuesday, September 9, 2014, in Cupertino, Calif. The iPhone 6 will have a screen measuring 4.7 inches, while the iPhone 6 Plus will be 5.5 inches. (Photo by Marcio Jose Sanchez/AP Photo)

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.

Smoke rises during an explosion from an Israeli forces strike in Gaza City, Saturday, November 17, 2012. Israel bombarded the Hamas-ruled Gaza Strip with nearly 200 airstrikes early Saturday, the military said, widening a blistering assault on Gaza rocket operations by militants to include the prime minister's headquarters, a police compound and a vast network of smuggling tunnels. (Photo Hatem Moussa/AP Photo)