Well, let's see... Living in San Francisco. If you paid for rent, groceries, and every thing in cash you could easily require 4k per month. That just so happens to be slightly below reporting amount. Do this enough and you'll be suspected of structuring your withdrawals to avoid the 5k withdrawal reporting threshold. I know the plural of anecdote is not data but it has been my experience that if you try to use cash for everything it gets you a nice little chat when you come in to make your monthly withdrawals and a threat to close your accounts that they will not give you in writing (I've asked). This is not just one institution and $deity save you if you have even so much have even looked at a bitcoin exchange let alone transacted with one. That was enough for US bank to threaten to close my accounts if I did any more business with them. If you want to transact in cash, just try to do it regularly and in volume, for everything. You'll only realise you're in a cage once you've run up against the invisible bars.