A woman wearing a kimono performs an uchimizu ritual outside a pachinko game parlor in Tokyo June 30, 2015. The splashing of water onto the hot asphalt in summer is an old Japanese tradition meant to cool down the air as the water evaporates. (Photo by Thomas Peter/Reuters)

In this Tuesday, January 22, 2019 photo, the wife of Saghir Khan,Anisa Khan, holds their daughter, Alfisa, at the family's house in Mirzapur. Saghir was beaten by a group of Hindus after being spotted transporting cows. (Photo by Bernat Armangue/AP Photo)

Members of the Bolivarian National Guard who joined Venezuelan opposition leader and self-proclaimed acting president Juan Guaido fire into the air to repel forces loyal to President Nicolas Maduro who arrived to disperse a demonstration near La Carlota military base in Caracas on April 30, 2019. Guaido – accused by the government of attempting a coup Tuesday – said there was “no turning back” in his attempt to oust President Nicolas Maduro from power. (Photo by Federico Parra/AFP Photo)

Armed Syrian Turkmen villagers are seen near the northern Syrian village of Yamadi, near the Turkish-Syrian border, Syria, November 24, 2015. Turkey shot down a Russian warplane near the Syrian border on Tuesday saying it had repeatedly violated its air space, one of the most serious publicly acknowledged clashes between a NATO member country and Russia for half a century. (Photo by Reuters/Stringer)

Several beaches along South Florida's Atlantic coast line were closed after thousands of sharks were seen migrating in the waters. The sharks were migrating from Boca Raton to Jupiter since the beginning of March, marine biologists told NBC Miami. Photo: A spinner shark swims just offshore on Midtown Beach in Palm Beach on Tuesday. (Photo by Jeffrey Langlois/Palm Beach Daily News)

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.

Toyoda Gosei Co Ltd's personal mobility concept airbag car "Flesby" is displayed at the 44th Tokyo Motor Show in Tokyo, Japan, October 28, 2015. (Photo by Yuya Shino/Reuters)

A competitor wearing a kilt and standing on a barrel throws a bowling ball between her legs during the “Brigaball” contest at the annual Bundanoon Highland Gathering, showcasing traditional Scottish events, held in the town of Bundanoon, located southwest of Sydney, April 9, 2016. (Photo by David Gray/Reuters)