An animal advocate lays in fake blood in a replica of a meat package with a label that reads “meat” during a protest “The meat is murder” in the Bulgarian capital Sofia on May 8, 2016. (Photo by Nikolay Doychinov/AFP Photo)

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.

Ng Sin Nee (L) and Lee Shin May (R) from Malaysia take pictures with the panoramic view of the city from the Sky Box at KL Tower, the world's seventh tallest telecommunications tower, in Kuala Lumpur on May 24, 2016. Officially opened on May 20, the Sky Box has been the latest attraction for tourists arriving to the Malaysian capital. It stands 300 metres above ground and can fit six people at any one time, and offers spectacular views of the Kuala Lumpur skyline, including the iconic Petronas Twin Towers. (Photo by Mohd Rasfan/AFP Photo)

Residents carry a slaughtered pig with a bamboo pole as they walk home on a street, which was shut to traffic due to ice, in Leishan county, Guizhou province January 31, 2015. Blizzards and icy rain that lasted for several days at the end of January have disrupted traffic, collapsed houses and decimated crops in central Chinese provinces, Xinhua News Agency reported. (Photo by Reuters/Stringer)

Chinese women wear face-kinis as they walk in to the water to swim at the beach on August 20, 2014 in the Yellow Sea in Qingdao, China. The locally designed mask is worn by many local women to protect them from jellyfish stings, algae and the sun's ultraviolet rays. (Photo by Kevin Frayer/Getty Images)

Kashmiri residents are evacuated in a tractor from their flooded neighborhood in Srinagar, India, Sunday, September 7, 2014. (Photo by Dar Yasin/AP Photo)

Hindu women worship the Sun god Surya in the polluted waters of the river Yamuna during the Hindu religious festival of Chatt Puja in New Delhi October 30, 2014. Hindu women fast for the whole day for the betterment of their family and the society during the festival. (Photo by Ahmad Masood/Reuters)

The northeastern United States sweltered this week in a scorching summer heat wave, complete with stagnant, sticky air and no winds for relief, forecasters said. Even in a summer already filled with stretches of very hot weather, this week will be stubbornly brutal, with no relief in sight until the weekend brings thunderstorms to the region, they said. "Plain and simple, this week may feel the worst of any week for this summer in the Northeast," said Accuweather.com meteorologist Alex Sosnowski. (Reuters)