Fat Burger Kid is a fast food burger restaurant in the Bedford Point district of Staunton Island, Liberty City in Grand Theft Auto III. Their advertisement which says "We've got bigger buns!" is a slang term for people with big butts, concerning the name of this restaurant. The name 'Fat Burger Kid' could be a reference to the American-Canadian burger restaurant, Fatburger.
The Fat Burger Kid logo is identical to that of Bolt Burgers.