This means you would have, say $100k in savings and transfer $10k at a time onto a centralized BTC debit card or something. With metals, you would do the exact same thing, move small amounts at a time onto a more centralized system if you need the convenience.
You could not do this and have this system exist without fees to transact. Not possible.
The point is you are not REQUIRED to expose yourself to any 3rd party middlemen using metals as a settlement layer like in bitcoin (the miners who demand rent). The energy input >0 required at all times for bitcoin to exist at all makes it a debt based system in practice. Metals are not a rent seeking vortex, they exist with no energy input; they're not a debt based system. You cannot use a debt based system as the base settlement layer. It's completely absurd to even suggest it.