Traditional grog was merely watered down rum. Not the tastiest of beverages, even when you have been spending months at sea without access to a well stocked pub. Pirate grog on the other hand (at least here in the world of Qucakers) is something a little more... potent.
Oh, and any corrolation between these strips and the Monkey Island series of games is purely unfounded. Completely true, but unfounded nonetheless!