An Argentina soccer fan watches the team lose to Saudi Arabia at a World Cup Group C soccer match, played on a large screen in the Palermo neighborhood of Buenos, Aires, Argentina, early Tuesday, November 22, 2022. (Photo by Gustavo Garello/AP Photo)

Two young boys kneel on stools on either side of a round table as one uses a match to this the other's cigarette, November 12, 1928. (Photo by FPG/Getty Images)

After their wedding ceremony, groom and bride, Nathan Mauger, Connie Young with family and friends, toast to the solar eclipse from the Rose Garden in Manito Park, Monday, August 21, 2017, in Spokane, Wash. (Photo by Colin Mulvany/The Spokesman-Review via AP Photo)

A helicopter from the Venezuela's Army takes part in a military parade to celebrate the 207th anniversary of Venezuela's independence in Caracas, Venezuela July 5, 2018. (Photo by Marco Bello/Reuters)

The Japanese punk rock garage quartet Otoboke Beaver perform at Maggie Mae's at the South by Southwest (SXSW) Music Film Interactive Festival 2017 in Austin, Texas, U.S., March 17, 2017. (Photo by Brian Snyder/Reuters)

Geraldine Moodie overcame harsh conditions to become western Canada’s first professional female photographer, capturing beautiful images in the country’s most remote regions. An exhibition, “North of Ordinary: The Arctic Photographs of Geraldine and Douglas Moodie”, is at Glenbow, Calgary, 18 February – 10 September. Here: Inuit woman, Kootucktuck, in her beaded attigi. Fullerton Harbour, Nunavut, February 1905. (Photo by Geraldine Moodie/The Guardian)

In this December 13, 2014 photo, Ricardo Alegria holds his donkeys by a leash as he yells to sell their milk in the streets of Santiago, Chile. Alegria, along with his brother Marco, has been selling fresh donkey milk for the past 25 years, and says it's recommended as a vitamin boost. Shot glass size cups of the drink sell for about $2 dollars. Half a liter, which is the most he says his donkeys can give in one day, sells for about $20 dollars. (Photo by Luis Hidalgo/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.