A that sort of scale, you need government permission to turn the banknotes back into legally recognized bank account balances. So if there's a 1% chance Switzer

A that sort of scale, you need government permission to turn the banknotes back into legally recognized bank account balances. So if there's a 1% chance Switzerland says "no, you can't actually just store cash in a vault instead", you're losing money on a risk-adjusted basis.