Participants pose for a photographers during the Miss Iraq Pageant in Baghdad, December 19, 2015. (Photo by Ahmed Saad/Reuters)

A lizard wears clothing and a headset at Pet Expo Thailand on May 07, 2023 in Bangkok, Thailand. Dogs take part in a skateboarding competition at Pet Expo Thailand, a four day exhibition held at the Queen Sirikit National Convention Center. Dogs were judged on form and agility and separated into novice and experienced categories. (Photo by Lauren DeCicca/Getty Images)

Yaroslava Mahuchikh, of Ukraine, makes an attempt in the women's high jump qualification at the the European Athletics Championships in Rome, Friday, June 7, 2024. (Photo by Andrew Medichini/AP Photo)

France's Alexia Richard looks up after falling in. loss to Spain in a beach volleyball match at the 2024 Summer Olympics, Wednesday, July 31, 2024, in Paris, France. (Photo by Robert F. Bukaty/AP Photo)

Motocross riders compete on the beach on October 15, 2023 in Weymouth, United Kingdom. The motocross event, which first came to the town in 1984, organised by Weymouth and Portland Lions Club in association with Purbeck Motocross Club, sees over 300 riders compete over a course along Weymouth beach. (Photo by Graham Hunt/BNPS)

A commuter gestures to Boris Johnson as he rides across Vauxhall Bridge in London, England on November 19, 2015. The London mayor was opening a cycle superhighway. (Photo by John Stillwell/PA Wire)

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.

Members of the Bearded Ladies Cabaret cross Broad St., before a march by supporters of Sen. Bernie Sanders, I-Vt., in Philadelphia, on the first day of the Democratic National Convention, July 25, 2016. (Photo by Tom Williams/CQ Roll Call/AP Images)