According to Carolyn Sissoko (syntheticassets.wordpress.com) this is how English banks used to operate as well. Back in the days when draughts were accepted or

According to Carolyn Sissoko (syntheticassets.wordpress.com) this is how English banks used to operate as well. Back in the days when draughts were accepted or not depending on the creditworthiness of the bank they were written by, it would have been laughable for a banker to not be super-wealthy, because how else would anyone recover their money in case of significantly correlated demand for liquidity? (This is long before the days of government guarantees preventing bank runs.)