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.

“Maho Beach is a beach on the Dutch side of the Caribbean island of Saint Martin, in the country of Sint Maarten. It is famous for the Princess Juliana International Airport adjacent to the beach. Arriving aircraft must touch down as close as possible to the beginning of Runway 10 due to the short runway length of 2,180 metres (7,150 ft), resulting in aircraft on their final approach flying over the beach at minimal altitude”. – Wikipedia

Photo: “AirFrance Boeing 747 landing in St. Maarten”. (Photo by Aurimas)

Lebanese university students wearing municipality police costume regulate the traffic in the village of Brummana, east Beirut, Lebanon, 23 June 2018. The touristic town of Brummana is making a daring move in anticipation of the crowded summer season, by forming a group of young policewomen wearing mini shorts to regulate the traffic. (Photo by Wael Hamzeh/EPA/EFE)

Bloodthirsty by Thomas P. Peschak, Germany/South Africa — winner, Behaviour: birds. When rations run short on Wolf Island, in the remote northern Galápagos, the sharp-beaked ground finches become vampires. Their sitting targets are Nazca boobies and other large birds. The finches rely on a scant diet of seeds and insects, which regularly dries up, so they drink blood to survive. ‘I’ve seen more than half a dozen finches drinking from a single Nazca booby,’ says Tom. Rather than leave their nests the boobies tolerate the vampires, and the blood loss doesn’t seem to cause permanent harm. (Photo by Thomas P. Peschak/2018 Wildlife Photographer of the Year)

Cosplay enthusiasts Alex Lawson, 20, attends the North East Manga and Anime Convention (NemaCon) dressed as Hunni Sempai at Middlesborough Town Hall on June 18, 2011 in Middlesbrough, England. Hundreds of Manga, Anime and Cosplay enthusiasts gathered for NemaCon 2011. Cosplay is short for Costume Play where players dress and perform roles from Japanese culture, Anime and Manga art characters. Many subcultures have also evolved inspired by video games, American cartoons and comics. (Photo by Christopher Furlong/Getty Images)

Dotty, a short-haired pointer belonging to Simon Kirby MP, devours a Parliament shaped cake watched by a jack russell Maximus (L) owned by Matthew Offord MP during the Westminster Dog of The Year competition in Victoria Tower Gardens on October 13, 2011 in London, England. The annual competition was won by Conservative MP for Tiiverton and Honiton Neil Parish with his Labrador Wilberforce, who was among the 15 Conservative MPs to enter versus only two Labour MP entrants. (Photo by Peter Macdiarmid/Getty Images)

“A girl arrives at the parking lot wearing tiny leather shorts and sits on the back of a bike with a horse power of more than 1,000 CC. Next to her a man gets ready to ride, wearing a skeleton mask. It’s more than a fashion show, it’s an extravaganza on two wheels along Chinese roads”. – Carlos Barria. Photo: A couple rides their motorcycle at the Qian Dao Lake rally, on May 11, 2013. (Photo by Carlos Barria/Reuters)