Women grieves near a bodies covered by tarp at the site of a landslide in Xinmo village in Maoxian County in southwestern China's Sichuan Province, Sunday, June 25, 2017. Crews searching through the rubble left by a landslide that buried a mountain village under tons of soil and rocks in southwestern China on Saturday found bodies, but more than 100 people remained missing. (Photo by Ng Han Guan/AP Photo)

Drag queen Courtney Act (real name Shane Jenek) attends the Celebrity Big Brother male contestants launch night at Elstree Studios on January 5, 2018 in Borehamwood, England. The drag queen was left over-exposed on last show after her outfit apparently fell off. (Photo by Mike Marsland/WireImage)

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.

Photographers gather to take pictures of pilot Andre Borschberg (C) ahead of the take off of Solar Impulse 2-a solar powered plane- in Nanjing, China, May 31, 2015. The world's largest solar-powered airplane, Solar Impulse 2, took off from eastern China's Nanjing on Sunday to continue its round-the-world voyage. The Swiss-made plane left Nanjing's Lukou International Airport at 2:39 in the early morning, with former fighter pilot Borschberg at the controls alone for the entire 8,200-kilometer flight from Nanjing to Hawaii, the toughest leg of its marathon adventure. (Photo by Reuters/Solar Impulse)

Boys pan for gold on a riverside at Iga Barriere, 25 km (15 miles) from Bunia, in the resource-rich Ituri region of eastern Congo February 16, 2009. Ituri is one of many areas of the country to have experienced bitter ethnic conflict between rival tribes in recent years. Massacres have left tens of thousands dead. It is this fighting that led U.S. authorities to take the unprecedented step of naming Congo in section 1502 of the Dodd-Frank financial regulation act, which says U.S.-listed companies that source gold, tungsten, tantalum and tin from Congo or its neighbours must assure the U.S. stock exchange regulator that their business is not helping fund conflict. (Photo by Finbarr O'Reilly/Reuters)

A moon bear rests in a pool inside an enclosure at the Vietnam bear rescue centre, in Tam Dao national park, Vinh Phuc, Vietnam, 09 July 2019. The center is operated by international organization Animals Asia. There are currently 184 bears living at the the Vietnam Bear Rescue Centre. It is estimated that there are less than a few hundred bears left in the wild in Vietnam. According to the latest data from the Ministry of Agriculture and Rural development, around 600 bears are still being kept on farms. In Vietnam, Animals Asia has rescued a total of 209 sun bears and moon bears. (Photo by Minh Hoang/EPA/EFE/Rex Features/Shutterstock)

Birds behaviour winner: Land of the Eagle by Audun Rikardsen, Norway. High on a ledge, on the coast near his home in northern Norway, Rikardsen carefully positioned an old tree branch that he hoped would make a perfect golden eagle lookout. To this, he bolted a tripod head with a camera, flashes and motion sensor attached, and built himself a hide a short distance away. From time to time, he left road‑kill carrion nearby. Very gradually – over the next three years – a golden eagle got used to the camera and started to use the branch regularly to survey the coast below. (Photo by Audun Rikardsen/2019 Wildlife Photographer of the Year)

In this November 16, 2018, file photo, Duane Townsend, left, shoots a pheasant at Special Friday Pheasant Hunts, sponsored by Southern Tulare County Sportsman's Association, at Lake Success Recreation Area in Porterville, Calif. A Utah man who has been in a wheelchair for more than three decades has created a pheasant hunt for people like him who need help getting into the outdoors. The Daily Herald in Provo reports that Clint Robinson broke his neck after being thrown off a horse at a rodeo 32 years ago. The event called “Wheelchairs in the Wild” pairs people that have physical disabilities with hunters who help them with whatever they need. Many go in off-road vehicles. (Photo by Chieko Hara/The Porterville Recorder via AP Photo/File)