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.

The burning Polaris of Jose Antonio Blangino of Argentina sits in the sand dunes during stage one of the 2012 Dakar Rally from Mar Del Plata to Santa Rosa de la Pampa on January 1, 2012 in Santa Rosa de la Pampa, Argentina. (Photo by Bryn Lennon/Getty Images)

Members of the Baby Dolls, a traditional Mardi Gras social club, dance during a second line parade honoring music legend Fats Domino, in New Orleans, Wednesday, November 1, 2017. The thousand-strong group marched and danced from Vaughn's Lounge to Domino's former home in the Lower 9th Ward. Domino, a New Orleans native, died this past week. (Photo by Gerald Herbert/AP Photo)

“Osama bin Laden has been killed in an American operation in Pakistan, President Obama announced from the White House on Sunday, calling his death “the most significant achievement to date in our nation's effort to defeat al-Qaida”. In a statement delivered from the East Room, Obama said a small team of U.S. personnel attacked a compound in Pakistan's Abbottabad Valley, where bin Laden had been hiding since late last summer. The U.S. team killed the 54-year-old al-Qaida leader after a firefight and “took custody of his body”, Obama said.” – Nwsource.com

Photo: Saudi dissident Osama bin Laden in an undated photo. October 10, 2001. Afghanistan's ruling Taliban lifted restrictions on Bin Laden, giving him permission to conduct “Jihad”, or holy war, against Afghanistan's enemies. (Photo by Getty Images)

“The Curiosity Mars rover has imaged a small metallic-looking protuberance on a rock. Visible (in the image below the green lines point to it), the protuberance appears to have a high albedo and even projects a shadow on the rock below...”

An ice covered entrance door to the international gene bank Svalbard Global Seed Vault (SGSV) near Longyearbyen on Spitsbergen, Norway, October 20, 2015. Two consignments of crop seeds will be deposited next year in a “doomsday vault” built in an Arctic mountainside to safeguard global supplies. The vault, which opened on the Svalbard archipelago in 2008, is designed to protect crop seeds, such as beans, rice and wheat against the worst cataclysms of nuclear war or disease. (Photo by Anna Filipova/Reuters)

Models dance during the presentation of Stella McCartney's Spring-Summer 2017 ready-to-wear fashion collection presented Monday, October 3, 2016 in Paris. (Photo by Francois Mori/AP Photo)

Hindu devotees laugh as they watch the religious festival of Lathmar Holi, where women beat the men with sticks, in the town of Barsana in the Uttar Pradesh region of India, March 17, 2016. During Lathmar Holi the women of Barsana beat the men from Nandgaon, the hometown of Krishna, with wooden sticks in response to their teasing. (Photo by Cathal McNaughton/Reuters)