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.

Toyoda Gosei Co Ltd's personal mobility concept airbag car "Flesby" is displayed at the 44th Tokyo Motor Show in Tokyo, Japan, October 28, 2015. (Photo by Yuya Shino/Reuters)

Rowers enter in Canaregio river during the 42nd Venice Vogalonga on May 15, 2016 in Venice, Italy. 42 years ago a group of Venetians, both amateur and professional rowers, came up with an idea of non-competitive race in which any kind of rowing boat can take part. The first Vogalonga began with the message to protest against the growing use of powerboats in Venice and the swell damage they do to the historic city. (Photo by Awakening/Getty Images)

Playboy Bunnies pose for a selfie at the premiere of “The Transporter Refueled” at Playboy Mansion in Los Angeles, California August 25, 2015. The movie opens in the U.S. on September 4. (Photo by Mario Anzuoni/Reuters)

People dressed in underwear run into a store to pick free clothes during a promotional event starting the summer sale at an outlet of the Desigual clothing retailer in Berlin, June 20, 2014. Desigual treated the first 100 customers with a free outfit if they stripped down to their underwear for the first day of the outlet's summer sale. (Photo by Thomas Peter/Reuters)

Masai women dressed in traditional clothes wear surgical masks as they wait for a ceremony marking World Elephant Day in the Amboseli National Park, Kenya, August 12, 2020. (Photo by Baz Ratner/Reuters)

Galveston resident Charlotte, 12, photographs her two-year-old beagle Sunny who reacts to high wind ahead of Hurricane Laura in Galveston, Texas, U.S., August 26, 2020. (Photo by Adrees Latif/Reuters)

Dana Clark, and her son 18 month old Mason, wait in line at City Hall as early voting begins for the upcoming presidential election in New Orleans, Louisiana, U.S., October 16, 2020. (Photo by Kathleen Flynn/Reuters)