Well, you can collect items that you can't eat like the Ancient Spring and Ancient Screw, so there's probably an NPC that can craft or repair items, or a way Link can do it himself at special spots (like cooking at a cooking pot).
Edit: I wish I found this gif earlier.
Source
Omg I love this Gif hahahah
But yes, I agree, I think they're gonna to like Skyward Sword and have someone who can upgrade/repair with objects. It's useful so I'll probably start keeping up my stuff early in the game.