Soken of FFXIV Doesn't Use Instruments (Eng Subs) 

imagine there is canon lying around square enix headquarters..

Seth Everman : I used a door as an instrument. You know, whatever I had standing around.

Mick Gordon: I used a chainsaw as an instrument, you know, whatever I had lying around.

I always loved his stories so if i find anymore I will definitely translate them!

so much truth in this comment

Its much harder to find uncooked rice in an office than at home. Empty cup ramen and mints, on the other hand...

O cara tem mais jeitinho brasileiro que muito br kkkk

That would require having the budget for rice XD - remember, this was during ARR's development so everything was string tight.

My guess would have to do with the specific sound the material the container is made out of makes. A foam or paper cup that is often used for cup noodles has a different sound to it than that of an aluminum can; slightly different sounds for different effects. It might be a good idea for a metallic sounding makeshift maraca, however. A smaller can for a more brief sound, and a partially filled tallboy can for a more hollow sound? I've messed around a little with this in my school's sound studios (media trade school, I study Game Arts but hang out a lot with sound production students) However the making of ARR music was for sure quite different from how the music is made now; I imagine he has plenty of fun trinkets to mess around with and make cool sounds out of now-a-days.

Look up Somen at FanFest 2019-he gave ‘Yanxia’ the same treatment, otomotone and all