Ummm, the Green Goblin isn't actually crazy. In the comics at least, it's just an act. The Green Goblin is a secret identity, while the Joker is jsut himself. Also, how exactly do they have the same weapons? Does the joker have a flying contraption and pumpkin bombs? I don't even know of any trademark weapons per se that the Joker has (unless you count nerve gas, and the Green Goblin doesn't use that if I'm not mistaken).
I didn't say they have the same weapons,I just said the weapons have a similarity between them.