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.

In this September 14, 2017 photo, young women pose for a photo inside their squatter building that used to house the Brazilian Institute of Geography and Statistics (IBGE) in the Mangueira slum of Rio de Janeiro, Brazil. Many lower-middle class Brazilians who gained ground during the boom years have since slid back closer to the poverty line. (Photo by Felipe Dana/AP Photo)

A firefighter passes through fire in a firefighting drill on December 7, 2021 in Aba Tibetan and Qiang Autonomous Prefecture, Sichuan Province of China. (Photo by Zeng Peng/VCG via Getty Images)

A SpaceX Falcon 9 rocket breaks the sound barrier as it launches the next batch of Starlink satellites (mission; Starlink 6-7), at 12:01 AM from Launch Complex 40 at the Cape Canaveral Space Force Station, Florida on Friday, July 28, 2023. (Photo by Joe Marino/UPI/Rex Features/Shutterstock)

Hundreds of people pack the Canaveral national seashore's Playalinda Beach as a United Launch Alliance Atlas V rocket, carrying a U.S. Navy communications satellite, lifts off from Complex 41 at the Cape Canaveral Air Force Station, Friday, June 24, 2016, in Cape Canaveral, Fla. The satellite is designed to significantly improve ground communications for U.S. forces on the move. (Photo by Craig Rubadoux/Florida Today via AP Photo)

A man makes traditional candy “Matang” in preparation for the upcoming Chinese Lunar New Year in Yuqing County, Zunyi, Guizhou Province, China, January 18, 2016. (Photo by Reuters/China Daily)

A motorist drives a car overloaded with vegetables and fruit on a street in Yaounde on July 25, 2022, prior to the French president's visit. (Photo by Ludovic Marin/AFP Photo)

Barber Herman Mulyana (R) gives a haircut to a customer while wearing protective attire made from plastic garbage bags at a barbershop in Bogor, Indonesia, 06 April 2020. The Trade Ministry of Indonesia issued a regulation temporarily recinding all requirements for the import of protective gear and medical equipment, to counter shortages of many items used to treat COVID-19 patients and prevent the further spread of the disease. (Photo by Adi Weda/EPA/EFE)