A participant shows off a belt buckle during the 20th annual Seattle Invitationals, an amateur Elvis impersonator competition, in Seattle, Washington January 23, 2015. The event drew hundreds of spectators for 20 contestants at the Crocodile, a venue in Seattle's Belltown neighborhood. (Photo by David Ryder/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.

Anja Rubik poses as she arrives for the screening of the film “Dolor Y Gloria (Pain and Glory)” at the 72nd edition of the Cannes Film Festival in Cannes, southern France, on May 17, 2019. (Photo by Stephane Mahe/Reuters)

Model Bella Hadid poses for photographers at the photo call for the film “Pain and Glory” at the 72nd international film festival, Cannes, southern France, Friday, May 17, 2019. (Photo by Arthur Mola/Invision/AP Photo)

Employee Victoria Livesey walks past Banksy's “Kate Moss 2005” on display at Bonhams on March 23, 2012 in London, England. The painting, estimated at GBP 30,000 – 50,000, USD 48,000 – 79,000 and 35,000 – 59,000 euros forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)

“Hey! I'm Thomas Shahan, an artist and macrophotographer from Oklahoma. In my spare time over the past few years, I've been shooting portraiture of local arthropods. Why would I devote countless hours to tramping through forests, fields and the like searching for insects and spiders? Well, despite some common beliefs, arthropods (members of the phylum Arthropoda – insects, spiders, crustaceans...) represent an endlessly varied, wildly beautiful and fascinating bunch of animals with surprisingly personable faces and behavior. Often, all it takes is simply inspecting their lives on a closer level to turn repulsion to reverence”. – Thomas Shahan

Photo: Adult Male Jumping Spider at Sunset – Phidippus mystaceus. (Photo by Thomas Shahan; Source: Flickr)

A chef cooks raw dog meat at a restaurant on July 5, 2005 in Gwacheon, South Korea. Dog meat is a traditional dish in Korea dating back to the Samkuk period (period of the three kingdoms BC 57 – AD 668). Although many recipes existed historically for dog meat, now chefs only make soups, or dishes using boiled or roasted meat. Koreans traditionally eat dog meat on the hottest day of the summer, for it's reputed benefits of virility, invigoration and health. (Photo by Chung Sung-Jun/Getty Images)