A winter swimmer, wearing a Santa Claus hat to celebrate the upcoming Christmas, reacts as he plays on a frozen lake at a park in Shenyang, Liaoning province, December 22, 2014. The characters on the hat read: “Shenyang Winter Swimming”. (Photo by Reuters/Stringer)

Hundreds of Nigerians celebrate at an intersection in the flashpoint northern city of Kaduna on March 31, 2015 the victory of main opposition All Progressives Congress (APC) presidential candidate Mohammadu Buhari. (Photo by Nichole Sobecki/AFP Photo)

A honor guard soldier stands at attention during a memorial religious service for those killed in the 1989 anti-communist uprising in University Square, in Bucharest, Romania, Wednesday, December 21, 2022. Participants and relatives of those killed marked the 33rd anniversary of the anti-communist uprising which started in Bucharest on Dec. 21, 1989 and left more than one thousand people dead and ended the rule of dictator Nicolae Ceausescu. (Photo by Andreea Alexandru/AP Photo)

USA's Jourdan Elizabeth Delacruz reacts as she competes in the women's 49kg weightlifting competition during the Tokyo 2020 Olympic Games at the Tokyo International Forum in Tokyo on July 24, 2021. (Photo by Edgard Garrido/Reuters)

Silver Medalists Thomas Daley and Noah Williams of Team Great Britain celebrate as they pose following the Diving medal ceremony after the Men’s Synchronised 10m Platform Final on day three of the Olympic Games Paris 2024 at Aquatics Centre on July 29, 2024 in Paris, France. (Photo by Marc Aspland/The Times)

A young lady blows a balloon during a federal conference of the German Pirate Party (Piratenpartei) on December 3, 2011 in Offenbach, Germany. (Photo by Ralph Orlowski/Getty Images)

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.

Determination: silver. Adam Pelech (No 3) of the New York Islanders and Brian Boyle of the Florida Panthers crash the boards during their game at Barclays Center in New York. (Photo by Al Bello/Getty Images)