A production department of a textile factory is seen abandoned in Kaduna, Nigeria November 3, 2016. President Muhammadu Buhari hopes to revive the once flourishing textile and leather industries in northern Nigeria to end the country's dependence on oil exports and diversify Africa's biggest economy. (Photo by Afolabi Sotunde/Reuters)

Thai officials arrive for morning alms as part of celebrations for the 68th birthday of Thai King Maha Vajiralongkorn Bodindrade​bayavarangkun, at Sanam Luang in Bangkok, Thailand, 28 July 2020. (Photo by Diego Azubel/EPA/EFE)

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.

An Indian Sikh devotee spits fire as he performs during religious procession ahead of the birth anniversary of the first Sikh Guru or master, Sri Guru Nanak Dev Ji, the founder of Sikhism, in Jammu, the winter capital of Kashmir, India, 21 November 2018. The birth anniversary of Guru Nanak Dev Ji will be observed on 23 November 2018. (Photo by Jaipal Singh/EPA/EFE)

Italian disabled dancer Simona Atzori (top) performs, before a special audience with disabled athletes led by Pope Francis, in Paul VI hall at the Vatican October 4, 2014. (Photo by Tony Gentile/Reuters)

An elephant decorated with a cloth walk in the annual Perahera (street pageant) at Rajamaha viharaya Buddhist temple in Colombo, Sri Lanka September 10, 2016. (Photo by Dinuka Liyanawatte/Reuters)

India: A sweeper cleans the side of a road near a replica of the Eiffel Tower amid heavy fog in the early morning in the northern Indian city of Chandigarh January 18, 2010. (Photo by Ajay Verma/Reuters)