A woman made-up with the technique of Body Paint seen during the 2nd Spanish tattoo artists Convention of the Only Tattoo Barcelona in Barcelona, Spain on March 17, 2018. (Photo by Ramon Costa/SOPA Images/Rex Features/Shutterstock)

Kyrgyz dancers perform in an event gathering bedouins and nomads from around the world as part of the annual King Abdulaziz Camel Festival in Rumah desert, northeast of the Saudi capital Riyadh, on March 19, 2019. (Photo by Fayez Nureldine/AFP Photo)

Russian woman takes selfie near military vehicle during the rehearsal for a military parade in Moscow, Russia, 29 April 2019. Russia will hold a Victory Day military parade on 09 May 2019 to mark the 74th anniversary since the capitulation of Nazi Germany in 1945. (Photo by Yuri Kochetkov/EPA/EFE)

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.

A little girl hangs three Siamese kittens on a washing line in a garden in Croydon, London. (Photo by Fox Photos/Getty Images). 14th July 1931

“Sky burial or ritual dissection was once a common funerary practice in Tibet wherein a human corpse is cut in specific locations and placed on a mountaintop, exposing it to the elements or the mahabhuta and animals – especially to birds of prey. The location of the sky burial preparation and place of execution are understood in the Vajrayana traditions as charnel grounds. In Tibet the practice is known as jhator, which literally means, «giving alms to the birds»”. – Wikipedia

Photo: A burial master chops bones of a body to feed vultures during a celestial burial ceremony on April 19, 2006 in Dari County of Guoluo Prefecture, Qinghai Province, northwest China. Celestial burial is a traditional funeral of Tibetan people, which began in the 7th century. (Photo by China Photos/Getty Images)

Indian commuters travel in a local train in Kolkata, India, Tuesday, February 26, 2013. Indian Railway Minister Pawan Kumar Bansal is presenting the country's rail budget for next fiscal year in the parliament Tuesday, Feb. 26, 2013. Indian railway network is one of the world's largest, with some 14 million passengers daily and some 64,000 kilometers (40,000 miles) of railway track cut through some of the most densely populated cities. (Photo by Bikas Das/AP Photo)

A visitor poses for a photo with a Crayon Shin-chan model during an exhibition at Joy City in Beijing May 5, 2015. The exhibition, which showcased fifty models of the Japanese cartoon character in different poses and expressions, will run from April 18 to June 22. (Photo by Jason Lee/Reuters)