The game disincentives the use if the items are limited in number and cannot be obtained from a replenishing source. IF you can stock up on the item somehow, it gives more breathing room to use it.
Aren't those specific items also presented as gifts from various characters in the game too? With a special letter from them and everything? They're not just generic consumables they were presents. This is one of those comedy bits where someone receives food from someone they adore and puts it in a box to save forever instead of just eating it.