Members of the Albert Battery perform a gun salute during the Anzac Day dawn service held by the Currumbin RSL on the Gold Coast in Currumbin, Australia, 25 April 2016. The Anzac day marks the landing of the Australian and New Zealand Army Corps (Anzac) troops at Gallipoli in what is today Turkey during WWI. World War One, also called the Great War, according to official statistics cost more than 37 million military and civilian casualties between 1914 and 1918. (Photo by Glenn Hunt/EPA)

Mosha, the elephant that was injured by a landmine, has her prosthetic leg attached at the Friends of the Asian Elephant Foundation in Lampang, Thailand, June 29, 2016. Mosha was 7 months old when she stepped on a land mine near Thailand’s border with Myanmar and lost a front leg. That was a decade ago... (Photo by Athit Perawongmetha/Reuters)

Photographer Carlos Barria holds a print of a photograph he took in 2005, as he matches it up at the same location 10 years on, in Lafitte, south of New Orleans, United States, August 16, 2015. The print shows Tyler Teal cleaning up his home, September 14, 2005, after Hurricane Katrina struck. In 2005, Hurricane Katrina triggered floods that inundated New Orleans and killed more than 1,500 people as storm waters overwhelmed levees and broke through floodwalls. (Photo by Carlos Barria/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.

Naki'o, a mixed-breed dog with four prosthetic devices, goes for a run in Colorado Springs April 12, 2013. Naki'o lost all four feet to frostbite when he was abandoned as a puppy in a foreclosed home. (Photo by Rick Wilking/Reuters)

Members of the police forces of Republic of Srpska march during a parade marking the 30th anniversary of the Republic of Srpska in Banja Luka, northern Bosnia, Sunday, January 9, 2022. This week Bosnian Serb political leader Milorad Dodik was slapped with new U.S. sanctions for alleged corruption. Dodik maintains the West is punishing him for championing the rights of ethnic Serbs in Bosnia – a dysfunctional country of 3.3 million that's never truly recovered from a fratricidal war in the 1990s that became a byname for ethnic cleansing and genocide. (Photo by Radivoje Pavicic/AP Photo)

New Market traders rescue an injured shopkeeper who got hurt during a clash with students from Dhaka college in Dhaka on April 19, 2022. (Photo by Munir Uz Zaman/AFP Photo)

Chad Rowley and his wife Susan race during the 22nd North American Wife Carrying Championship at Sunday River Resort in Newry, Maine, on October 9, 2021. Couples compete on a 278-yard (254-meter) obstacle course for a prize of wife's weight in beer and five times her weight in money. Winners are invited to the world championship in Finland where the sport originated. (Photo by Joseph Prezioso/AFP Photo)