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.

Senator Barack Obama (D-IL) (R) stands in front of Senator Hillary Clinton (D-NY) as they arrive for U.S. President George W. Bush's annual State of the Union speech to a joint session of Congress at the U.S. Capitol in Washington in this January 23, 2007 file photo. Hillary Clinton announced her second run for the presidency on April 12, 2015 starting her campaign as the Democrats' best hope of fending off a crowded field of lesser-known Republican rivals and retaining the White House. (Photo by Larry Downing/Reuters)

American actress Emma Stone uses her mobile phone to touch up her makeup during the 96th annual Academy Awards ceremony at the Dolby Theatre in the Hollywood neighborhood of Los Angeles, California, USA, 10 March 2024. The Oscars are presented for outstanding individual or collective efforts in filmmaking in 23 categories. (Photo by Caroline Brehman/EPA/EFE)

The scene in Star Lane, Dunmow, Essex, after a steam traction engine from Sussex on its way to the Saffron Walden Crank Up weekend steam show, crashed into a private dwelling on Friday, April 21, 2023. (Photo by Nicholas.T.Ansell/PA Images via Getty Images)

Soldiers and firefighters carry the body of Chilean President Salvador Allende, wrapped in a Bolivian poncho, out of La Moneda presidential palace after it was bombed during a coup by Gen. Augusto Pinochet in Santiago, Chile, September 11, 1973. (Phoot by El Mercurio/AP Photo)

On the afternoon of the January 3, 2025, seagulls are gathering around a child holding shrimp crackers at Haeundae Beach in Busan, South Korea. (Photo by Dong-Hwan Kim)

A young macaque perches on a pole, observing nearby tourists while eating some seeds in Jigokudani Yaen-koen wild macaque monkey park on February 16, 2015 in Yamanouchi, Nagano, Japan. (Photo by Manuel Romaris/Getty Images)

Minoru Suzuki and Sanshiro Takagi, wrestlers from Japanese professional wrestling promotion DDT Pro-Wrestling, fight inside Tokaido Shinkansen bullet train from Tokyo to Nagoya during a wrestling show in Japan on September 18, 2023, in this handout photo released by JR Tokai (The Central Japan Railway Company). (Photo by JR Tokai/Handout via Reuters)