A Snowboarder participates in a waterslide contest, which consists of gliding over a water pool embedded in snow, during the closing event of the ski resort of Nendaz, southwestern Switzerland, Monday, April 21, 2014. (Photo by Maxime Schmid/AP Photo/Keystone)

A sloth peeks out from behind a door on a floating house in the “Lago do Janauari” near Manaus, Brazil, Tuesday, May 20, 2014. Manaus is one of the host cities for the 2014 World Cup in Brazil. (Photo by Felipe Dana/AP Photo)

Kenyan women protest for the right to wear whichever clothes they want, at a demonstration in downtown Nairobi, Kenya Monday, November 17, 2014. A recent incident in which a mob of men surrounded a woman and tore her clothes off, leaving her naked on the street in front of a bus stop after alleging that she was improperly dressed, is one of several such videos that have surfaced online in recent days leading to a groundswell of anger that on Monday prompted around 1000 demonstrators, including a number of men supporting the women's cause, to march through the capital and protest online using the hashtag #MyDressMyChoice. (Photo by Ben Curtis/AP Photo)

21 year-old Chanel Tapper, with the amazing tongue and 35 year-old Aevin Dugas, with the beautiful hair was certified as world record breakers for the world’s longest tongue and the world’s biggest afro in the Guinness Book of World Records. (Photo by Guinness World Records)

A baboon clings to the leg of an internally displaced boy at a camp on the outskirts of the town of Qol Ujeed, on the border with Ethiopia, Somaliland April 17, 2016. Across the Horn of Africa, millions have been hit by the severe El Nino-related drought. In Somaliland and its neighbouring, also semi-autonomous, Puntland region, 1.7 million people are in need of aid, according to the United Nations. In Somaliland itself, the most affected areas include the northwest Awdal region bordering Ethiopia. (Photo by Siegfried Modola/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.

An Indian child artisan carries an idol of elephant-headed Hindu God Ganesha at a workshop ahead of Ganesh Chaturthi festival in Chennai, India, Saturday, September 7, 2013. Ganesh Chaturthi, which begins from September 9, is celebrated as the birthday of Lord Ganesha who is widely worshiped by Hindus as the God of wisdom, prosperity and good fortune. (Photo by Arun Sankar K./AP Photo)

Border between Sweden and Norway at Moldusen. An approximately 20-meter wide clearing in the forest separates the two Scandinavian nations, consequently cutting Finnskogen in two. Grue Finnskog 2016. (Photo by Terje Abusdal/The Washington Post)