A runner dressed as Spiderman poses before the annual “Sao Silvestre Run”, an international race through the streets of Sao Paulo, Brazil on December 31, 2021. (Photo by Carla Carniel/Reuters)

A woman plays on a swing on the beach in Santa Monica, Calif., Wednesday, June 22, 2022. (Photo by Jae C. Hong/AP Photo)

The Balance Bike Quad Eliminator being run (and organised) by GT Bicycles at the Malverns Classic, Start Line, Eastnor Deer Park, Eastnor, in Herefordshire on Friday 26th August 2022. Youngsters enjoy the thrills & spills of balance bike riding as they partake in the annual event held in rural Herefordshire. The thrills and spills as rider No. 013, Kelia Ranes tries hard to avoid a fallen competitor. (Photo by Richard Stanton/The Times)

Performers of circus company Circa perform during a photocall for the Edinburgh Festival Fringe on Calton Hill on August 1, 2017 in Edinburgh, United Kingdom. (Photo by Murdo MacLeod/The Guardian)

«Underwater». Laurie Simmons discovered this silicone sеx doll in a shop while on holiday in Japan and was immediately interested in the type of generic beauty their looks could add to her work. She went on to create the Love Doll series, in which she places silicone sеx dolls in positions that explore a woman’s interior life. (Photo by Laurie Simmons/Salon 94/The Guardian)

A male puma, named Bordo arrives for an examination and tests at a veterinary in Brasilia, Brazil, 31 October 2017 (issued 01 November 2017). Bordo, a young male puma, captured when he was a cub, will become the first animal of his species to be released in a sanctuary in the Brazilian savannah in Goias State close to Brasilia. The sanctuary, a preserve for wild cats, is in the first phase and is located on private lands but state funded. (Photo by Joedson Alves/EPA/EFE)

A soldier walks on the bank of the river in central Pyongyang, North Korea on April 16, 2017. (Photo by Damir Sagolj/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.