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 February 22, 2021, file photo, climate activist Disha Ravi, 22, travels in a car as she is taken to a court in New Delhi, India. To her friends, Ravi, was most concerned about her future in a world where temperatures are rising. But her life changed last month as she became a household name in the country, dominating news coverage after police charged her with sedition, a colonial-era law which carries a sentence up to life. Her alleged crime: sharing an online document to help amplify months-long farmer protests in India on Twitter. She was released after 10 days in custody. (Photo by Dinesh Joshi/AP Photo/File)

A Hawker Hurricane Mk XIIa 5711 (G-HURI) fighter aircraft prepares to perform an aerobatic display at the IWM Duxford on October 18, 2012 in Duxford, England. The aeroplane, similar to those that defended British shores during the Battle of Britain in World War II, is due to be auctioned by Bonhams in their sale of “Collectors' Motor Cars and Automobilia” at Mercedes-Benz World Brooklands on December 3, 2012. The plane was built in 1942 and joined the Royal Canadian Air Force the following year, where it remained for the duration of the war, it is expected to fetch up to 17 million GBP. (Photo by Oli Scarff)

Pooh, a one-year-old cat, who lost his hind legs in an accident and has been given bionic paws, walks in a vet clinic in Sofia on January 31, 2017. Pooh, who is thought to have lost his legs in a car or train accident last April, is back on the prowl thanks to Bulgarian veterinary surgeon Vladislav Zlatinov. He is the first vet in Europe to successfully apply the pioneering method of Irish neuro-orthopaedic surgeon Noel Fitzpatrick, who shot to fame in 2009 when making Oscar the first bionic cat by fitting him with new hind legs in Britain. (Photo by Nikolay Doychinov/AFP Photo)

The expertly colourised shots were brought to life by French bank technician, Frédéric Duriez (51). The images were provided by the Valois collection which belongs to the BDIC. “By colourising these photos, I reduce the time that separates us today from this conflict”, said Frédéric. Here: Car cannon sections in firing position, Auxi-le-Château. (Photo by Frédéric Duriez/BDIC/Mediadrumworld.com)

Members of the public continue to pay their respects at the scene of a hit and run following civil disturbances in the Winson Green area on August 12, 2011 in Birmingham, England. Police are continuing investigations after three people – reportedly trying to protect shops from rioting and looting in Dudley Road – were struck by a car and killed during rioting. Police have so far arrested over 1,000 people following rioting which erupted over a four-day period across the UK. (Photo by Jeff J Mitchell/Getty Images)

A black bull sarcophagus stands at Puri Ubud during the Hindu Royal cremation – also know as the Pengabenan – for the late Anak Agung Niang Rai, mother of Gianyar Regent, Tjokorda Oka Artha Ardana Sukawati, at Puri Ubud in Gianyar Bali on August 17, 2011 in Ubud, Bali, Indonesia. Niang Rai died in a Denpasar hospital in May; her actual cremation will take place on August 18 and will involve a nine level, 24m high 'bade' or body carring tower, made by upto 100 volunteers from 14 local villages. It will be carried to the cremation by 4500 Ubud residents. (Photo by Ulet Ifansasti/Getty Images)