A Palestinian demonstrator (R) shouts at an Israeli soldier, during clashes with Israeli troops at the Qalandiya checkpoint, on June 5, 2011 between Jerusalem and the West Bank city of Ramallah. The clashes come on the 44th Anniversary of the Arab defeat in the 1967 Six Day War of the Middle East. (Photo by David Vaaknin /Getty Images)

A policeman stands near a burning vehicle during clashes between supporters of former prime minister Imran Khan and riot police near Khan's house to prevent officers from arresting him, in Lahore on early March 15, 2023. Pakistan police appeared on March 15 to have given up an attempt to arrest former prime minister Imran Khan, ending a siege of his residence after violent clashes with hundreds of his supporters. (Photo by Arif Ali/AFP Photo)

New Market traders rescue an injured shopkeeper who got hurt during a clash with students from Dhaka college in Dhaka on April 19, 2022. (Photo by Munir Uz Zaman/AFP Photo)

A protester clashes with riot police officers during a protest against the Asia-Pacific Economic Cooperation (APEC) Summit 2022, near the Democracy Monument in Bangkok, Thailand on November 18, 2022. (Photo by Tanat Chayaphattharitthee/Reuters)

Combine harvesters work on a wheat field of the Solgonskoye farming company near the village of Talniki, southwest from Siberian city of Krasnoyarsk, Russia, August 27, 2015. Russia, one of the world's top wheat exporters, will harvest its third-largest grain crop in post-Soviet history this year, leading Russian consultancy SovEcon said on August 27 after upgrading its forecast. (Photo by Ilya Naymushin/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.

People walk with their arms raised as security forces restore order in Nice, France on July 14, 2016. (Photo by SIPA Press/Rex Features/Shutterstock)

A demonstrator is detained by police officers during clashes in downtown Barcelona, Spain, Friday, October 30, 2020. Clashes have erupted in a central Barcelona square between anti-riot police and hundreds who had gathered to protest the mandatory closure of bars, restaurants and other businesses in the latest effort to rein in on coronavirus outbreaks. (Photo by Joan Mateu/AP Photo)