At least in the first two editions, shamans with Raven are describes as either obese or rail-thin, and either way being almost unable to turn down an offer of food.
Orks and Trolls in general require much more food than Humans or Elves. There is also a biological augmentation known as the "suprathyroid" gland, which improves physical attributes significantly at the cost of vastly increased caloric intake. This is touched upon more in some of the novels.
The Increased Consumption Disadvantage means a character will eat much more than their size and weight would imply.
Similarly, the "Gluttony" drawback, which can be taken with the "Skinny" drawback. Leading to a character who needs to make a will save not to eat any food they see, but (unless you buy off the Skinny drawback) never even hits average weight.
Space Marines inside Warhammer 40,000, though they are more ridiculously muscled than thin. Their Super SoldierBio-Augmentation releases hormones in their body for the muscle growth, but such growth still needs to be fueled by their daily feasts (by our standards) and wildlife hunted. They also are able to be Extreme Omnivores, known to eat healthy meals of concrete and metal (and have super-tough bones that only work because their diets are laced with ceramic-based chemicals).
The biggest eater of all the Space Marines was the primarch of the Space Wolves Leman Russ. How? He was the only primarch to beat the Emperor in something, twice, namely an eating contest, and a drinking contest.
The Tyranids, also from Warhammer 40000, are the pinnacle of big eaters. A race of intergalactic insects who descend on the Milky Way with the intent of devouring all life and natural resources in order to fuel their hyper accelerated evolution process. And if you thought that was enough to qualify for this trope, it is hinted that the Tyranids have already successfully carried out this plan in the past, effectively strip mining several galaxies prior to their arrival here.
Some of the books for Werewolf: The Forsaken state that the Uratha have greater appetites than most (partially because they're part-wolf, partially because of the metabolism required for their Healing Factor). As a result, four meals a day is normal for most of them.
Novas in Aberrant have both hyper-enhanced metabolisms that keep their bodies trim and a need for vast caloric intakes to help fuel their Quantum powers. One mentions once having gone to Burger King for 50 Whoppers And a Diet Coke.
The Atlanteans from Conspiracy X need to eat a lot of calories to power the nanomachines that keep them immortal and give them their superpowers.
Gurps has the Gluttony disadvantage which can be taken with the Overweight, or Heavily Overweight, disadvantage. If the character buys off the Gluttony disadvantage, he won't lose any weight.
The Ogres of Warhammer have this as their hat, so much so they have twice daily feasts. And they worship a god of gluttony. There is even a point in one of the books where two Ogres eat a 5-ton Rhinox in one sitting; by the time they are done they both have more than their entire body mass in raw meat crammed into their stomachs.
One dissection of a fallen ogre, itemising the stuff in its stomach, turned up the skeleton of an entire horse.
Ogres from Changeling: The Lost don't have to be fat, but it's hard to be thin when you are designed to eat anything on the planet.
Sesus "The Slug" Nagezzer from Exalted, whose road to obesity was similar to Henry VIII (see below) — a war wound left him unable to exercise and work off the massive amounts of food he continued to eat every day.
The Tarrasque of Dungeons & Dragons fame. As of 4th edition, it's an unstoppable curse laid by a being older than the gods that plagues the world. It exists only to eat, and it can eat entire kingdoms before going back to sleep.