Alan Swinney points a gun during clashes between groups like Proud Boys and Patriot Prayer, and protesters against police brutality and racial injustice in Portland, Oregon, U.S., August 22, 2020. (Photo by Maranie Staab/Reuters)

AFC Bournemouth's Marcus Tavernier celebrates scoring their first goal with Adam Smith during the Premier League match between AFC Bournemouth and Fulham FC at Vitality Stadium on April 01, 2023 in Bournemouth, England. (Photo by Paul Childs/Action Images via Reuters)

Nature, singles winner: Frogs with their legs severed struggle to the surface, surrounded by frogspawn, after being thrown back into the water in Covasna, Romania. (Photo by Bence Mate/World Press Photo 2019)

Natalia Williams dressed as Corpse Bride Emily and Tony Knight as a Mandalorian, arrive at the Bradford Unleashed Comic-Con, an entertainment and comic book convention in England on March 8, 2020. (Photo by Danny Lawson/PA Images via Getty Images)

A child yells, “I don't want go!” as a state employee attempts to remove her from another branch of the Orphanage of the Church of Bible Understanding, in the Kenscoff area outside Port-au-Prince, Haiti, Friday, February 14, 2020. (Photo by Dieu Nalio Chery/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.

Vegetarian 19-year-old model Courtney Stodden gets ready to serve veggie hot dogs wearing a lettuce bikini during a People for the Ethical Treatment of Animals (PETA) free veggie dog handout on Capitol Hill in Washington, DC, July 16, 2014. (Photo by Jim Watson/AFP Photo)

People stand around a leopard with its head stuck in a vessel in Rajsamand district of Rajasthan state, India, Wednesday, September 30, 2015. The leopard's head got stuck when it attempted to drink water from the pot, according to news reports. Forest officials tranquilized the animal and sawed off the vessel later in the day. (Photo by Kabir Jethi/AP Photo)