Few things symbolize this better than the outrageous requests they often make when on tour.
These requests are referred to as "riders", and appear in the contract a tour venue receives in advance of the artist's arrival. These contract riders specify the physical conditions that the singer/band requires to be in place before arriving to perform. Stage lighting settings, sound equipment, furnishings, etc — that kind of stuff.
And these rider requests can get pretty funky – often extremely so — when it comes to backstage perks the performers want.
For example: A wooden pond filled with koi carp (Eminem). A driver who will not speak or make eye contact (Katy Perry). 20 white kittens and 100 doves (Mariah Carey). Seven dwarves (Iggy Pop). 50,000 bees (Slayer). A sub-machine gun (Mötley Crüe). And, yes, even a great white shark (Hank III).