A woman walks past as South Korean soldiers participate in an anti-chemical and anti-terror exercise as part of the 2023 Ulchi Freedom Shield (UFS) at subway station on August 22, 2023 in Seoul, South Korea. The 11-day exercise, which features drills including the handling of chemical and biological attacks, is a regular joint exercise between U.S. and South Korean troops. (Photo by Chung Sung-Jun/Getty Images)

Elise Graham takes part in the World Bog Snorkelling Championships 2017 with a rubber duck on her back on August 27, 2017 in Llanwrtyd Wells, Wales. The competition draws competitors from all over the world and is now in its 32nd year. (Photo by Matthew Horwood/Getty Images)

An Iraq fan poses before the World Cup 2022 Qualifier 2nd round Group C football match between Iraq and Iran at Amman International Stadium in Amman, Jordan on November 14, 2019. (Photo by Muhammad Hamed/Reuters)

A girl carries a rifle as she attends a rally by followers of the Shi'ite Houthi movement commemorating the death of Imam Zaid bin Ali in Sanaa, Yemen October 26, 2016. (Photo by Khaled Abdullah/Reuters)

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.

Several beaches along South Florida's Atlantic coast line were closed after thousands of sharks were seen migrating in the waters. The sharks were migrating from Boca Raton to Jupiter since the beginning of March, marine biologists told NBC Miami. Photo: A spinner shark swims just offshore on Midtown Beach in Palm Beach on Tuesday. (Photo by Jeffrey Langlois/Palm Beach Daily News)

Armed Syrian Turkmen villagers are seen near the northern Syrian village of Yamadi, near the Turkish-Syrian border, Syria, November 24, 2015. Turkey shot down a Russian warplane near the Syrian border on Tuesday saying it had repeatedly violated its air space, one of the most serious publicly acknowledged clashes between a NATO member country and Russia for half a century. (Photo by Reuters/Stringer)

A photograph made available on 30 September 2016 showing wind turbines at the site of the highest wind park in Europe at the Griessee, near the Nufenenpass in the Swiss south Alpes, Valais, Switzerland, on 23 September 2016. The four wind turbines of this wind park were developed by the company SwissWinds GmbH and are inaugurated on, 30 September 2016. (Photo by Olivier Maire/EPA)