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.

Parked scooters and motorcycles in a line on January 13, 2012 in London, England. Statistics showed a 12% increase in scooter registration in 2011, with cost savings on petrol, parking and congestion charge (in London) believed to be the primary factor. (Photo by Matthew Lloyd/Getty Images)

British housewives toss pancakes in skillets as they run through the streets of Olney, England, in the community's annual race which follows a 500-year-old tradition, February 6, 1951. Mrs. Isabel Dix, 22, extreme right, won the race covering the 415 yards from the Parish pump to the door of Sts. Peter and Paul church in one minute, 12.1 seconds. (Photo by AP Photo)

Ukrainian soldiers fire the D-30 artillery to Russian positions in the direction of Klishchiivka as the Russia-Ukraine war continues in Donetsk Oblast, Ukraine on August 12, 2023. (Photo by Diego Herrera Carcedo/Anadolu Agency via Getty Images)

The Guinness World Record for the fastest tortoise in the world is held by Bertie, a South African leopard tortoise, who covered 5.49 metres in 19.59 seconds. (Photo by Paul Michael Hughes/Guinness World Records/PA Wire Press Association)

Three young women preparing a guy. They are sitting him on a keg labelled “gun powder”. (Photo by Fox Photos/Getty Images). 1929

A storm trooper feeds a walker in the grass, taken in Glasgow, Scotland, December 2016. Tiny Storm Troopers and a mini Darth Vader are captured doing everyday activities – from taking a bath, to wrapping presents. Scottish Artist and Photographer, David Giliver created these scenes over a period of two years using toys and miniature props. (Photo by David Gilliver/Barcroft Images)

A worker cleans the statue of Yuri Gagarin, the first person who flew to space, ahead of Cosmonautics Day celebrated on April 12, in Moscow, Russia, Wednesday April 10, 2019. Cosmonautics Day marks when Soviet cosmonaut Yuri Gagarin became the first man to fly in space, in 1961, orbiting the earth once before making a safe landing. (Photo by Maxim Marmur/AP Photo)