This picture taken on May 24, 2019 shows Mariam the dugong as she is cared for by park officials and veterinarians from the Phuket Marine Biological Centre on Libong island, Trang province in southern Thailand. An orphaned baby dugong rescued off a beach in Krabi province is Thailand's newest star, capturing the hearts of millions on social media and igniting an awarness for ocean conservation as authorities hand-raise the young mammal. (Photo by Sirachai Sirachai Arunrugstichai/AFP Photo)

Women take pictures by a vintage car during the 2019 GUM Motor Rally featuring classic cars in Moscow, Russia on July 28, 2019. The youngest car at this year’s rally is 35, the oldest – a GAZ-A convertible – is 85. (Photo by Artyom Geodakyan/TASS via Getty Images)

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 market trader in Gaibandha in Bangladesh on September 25, 2019, surrounded by bottle gourd vegetables, which sell for around 3p ($ 0.04) each. (Photo by Solent News)

An alligator named Muja is seen in its enclosure in Belgrade's Zoo, Serbia, August 14, 2018. Muja is officially the oldest American alligator in the world living in captivity. He was brought to Belgrade from Germany in 1937, a year after the opening of the Zoo. Muja survived three bombings of Belgrade, the Second World War and all hardships the Zoo went through. (Photo by Marko Djurica/Reuters)

A vender arranges goods for sale at a market on the outskirts of Buenos Aires, Argentina, Wednesday, January 10, 2024. (Photo by Natacha Pisarenko/AP Photo)

A snow leopard looks on from an inside of a cage, after being captured from the southern plains of Nepal and brought to the central zoo, which wildlife experts say is rare for the animal that is found in the higher altitude, in Kathmandu, Nepal on January 26, 2024. (Photo by Navesh Chitrakar/Reuters)

It doesn’t make for the most flattering photoshoot, but there is a reason these zebras at Lewa wildlife conservancy in Kenya in the second decade of August 2025 are stood head to tail: they use their tails to swat flies from each others’ faces. (Photo by Andrew Campbell/Solent News & Photo Agency)