I don't think there is enough to spend munny on in Kingdom Hearts. At first you may need to buy some Potions/Hi-potions/Ethers but soon you get plenty of these from battles or chests, and I never needed to use them that often anyway. Then there are a few accessories and weapons you can buy in the shop, but soon you receive some that are much better than those anyway.
I'm working on levelling up to Lv.99 and I'm at Lv.81, but I've had the maximum munny for ages now. And the problem is there's just nothing to do with it! I have far too many Hi-potions that I can't pick up more, and there's little point selling them when I have maximum munny.
In FFVII you had the Gold Saucer to spend your money at, or you could buy that house, and in FFX there was the bribing that you'd need money for, and getting clear spheres. There was incentive to need money.
But in this game, I don't see much point for munny at all, especially after a while into the game. It's sort of disappointing. What does everyone else think?