Easy carbs and abundance of it. Before it was hard to find too much food for a common person.
A slice of cake is, in fact, an "excessive amount" - it's more food than a pound of cheese.
Eating a pound of cheese does, indeed, feel "excessive", while a slice of cake (or two) is just a chaser after a full meal for most people.
Diesel fuel has a huge amount of calories, but your body obviously can't process it properly.