So because of space magic every quality of the game has to be utterly unrealistic? Having a limited ammo supply adds a level of strategy to the game. That way you can't sit back with rockets or a sniper and have the game be too easy. With the necessity of having to ensure you have reserve ammo it means you have to be more efficient while you shoot. Can you understand how having an unlimited ammo supply would make the game too easy? (I know it's not that difficult already)