Three hots and a cot in a U.S. jail would be an improvement over whatever standard of living Somalia offers without the ransom money. Get the captain back and let them slink back to their sewer. They're the laughing stock of the other pirates as it is. "Ha, ha, ha Mohammed. Can't take the ship. Can't ransom the captain. Can't do anything right."
I just wouldn’t let them try and spend their sack of conterfeits. Either jail ‘em or blow ‘em out of the water, they cannot be allowed to get away with piracy on the high seas.