In the scene when Shaggy and Scooby have just rescued Fred from the hook, the gang is standing there and Fred's arm is hanging there without a hand.
Shaggy: The sea water's boiling, Scoob, I wonder what pirates like in their stew?
Shaggy: Hey yeah, ghosts like chains, and what else? Oh yeah, some ashes from the stove, you know this could be real good? What else do pirates like?
Shaggy: Cobwebs! Aha, delightful. Now did we forget anything?
Shaggy: Soap? I hardly use it myself, but why not?
(about their phony breakfast food service)
Butler: At 11 o'clock at night?
Shaggy: Yeah, that way you don't have to get up in the morning to eat it.
Shaggy makes a rare reference to his being a hippie while winging the ingredients of Ghost Pirate Stew, one of which is a bar of soap. He admits to seldom having a need for soap personally. But if his hygiene is that bad, how can the rest of the gang spend all their time cooped up in the Mystery Machine with him?
First time the whole gang is captured.
Adapted into the comic book story "The Ghost Of Redbeard" (Gold Key issue #6, June 1971; reprinted in issue #26, August 1974).