In your thread it claims that Shaggy is skinny. He is not. It was revealed in one of the Scooby Doo movies that Shaggy is actually extremely obese and that he just wears a massive belt tied really tied to keep himself from looking fat.
-- I'm not kidding.
Yea, you watch too much Scooby doo dude.
Though that does explain how he can keep eating and eating and eating...