Banking at the corner market

 I do it, as my tax issue is still resolved.

Property taxes are coming, so I dump 200 in surplus onto my market tab.  Anything I need, he can get. When taxes come, I pay the taxes and he will carry up to 300. He runs a good book, risk equalized entry and exit. The transaction costs are hidden in the convenience fee., which varies among local stores.  I am a matched set, it is unlikely I will observe a better deal with the same convenience level. He is also an ex mathematician, knows banking theory.

If I take this fixed income and dump half of it on that market, my ATM fees drop by 50% on a ratio basis, the banks are losing a 2%  extra fee they would earn over both ends of the deal. That is shadow banking, avoid the seigniorage taxes.