Quote Originally Posted by SamRF View Post
Flute can be stored in places hidden from sight due to its cylinder shape
I have to assume that you've never actually carried a flute, especially one that isn't designed to be disassembled. They're not exactly easy to just shove into a pocket. And whether a player could hide one at all depends on their character's race and glamour; I'd have to be wearing a trench coat for that to work.

Relatedly, there's also the harp that bards pull out of thin air to use their songs. Which they still do even when using a bow that has a harp built in, like the Artemis Bow (which, lore-wise, was specifically made to avoid this issue by quickly folding and unfolding, but it still goes away to use a song).

Either way, though, you don't see them when you don't need them. So why can't the lunch box pull the same disappearing act?