Damn, Oda really wants to make it so that no other Straw Hat other than Luffy can contribute to anything.
"As a child, Monkey D. Luffy was inspired to become a pirate by listening to the tales of the buccaneer "Red-Haired" Shanks. But Luffy's life changed when he accidentally ate the Gum-Gum Devil Fruit and gained the power to stretch like rubber...at the cost of never being able to swim again! Years later, still vowing to become the king of the pirates, Luffy sets out on his adventure...one guy alone in a rowboat, in search of the legendary "One Piece," said to be the greatest treasure in the world..."
This is shueisha's sunmary for one piece. Do you see any other SHPs here? No, this is Luffy's journey others have alinged with him to fulfill his and their's dream. Why are you so hurt at the obvious?