SmartAleq, are you perhaps a small business owner? I’ve asked a few proprietors who don’t accept credit cards why they don’t; paying in cash is really inconvenient for me, and I’m sincerely curious about why a merchant would put up barriers to its customers. I’ve asked maybe seven or eight of them about this, and every one essentially saw credit card processing fees not as overhead (like rent and the cost of inventory) but an arbitrary reduction in the profit the merchant has rightfully earned.
Your point about the grave errors made by every non-cash-accepting business (like, you know, Amazon and Apple’s app/music/media sales business) is more than a bit silly. I can’t help wondering whether you feel you have some personal stake in cash payments. Maybe not, but I thought I’d ask.
Hmm…no, that’s not what you said. You said merchants were obligated to take cash or propose a non-cash, non-credit-card alternative that the buyer finds acceptable.
I’m pretty sure we agree that civil forfeiture, (a uniquely American practice, as Nava points out), has dire implications for due process and the rule of law. But do you really think a bundle of cash is less likely to be seized in civil forfeiture than money in a bank account? Stashed bundles of cash—lockbox or no—are routinely seized in civil forfeiture. I wouldn’t be surprised if the value of cash siezed that way dwarfs that of bank accounts siezed under the same (odious, IMHO) pretense.
You suggest that cash would come in handy if bank accounts ceased to exist, but I’m struggling to imagine a sudden bank-account-ending scenario that doesn’t also make cash worthless.The US dollar is a fiat currency, remember? 
I can see why the collapse of the commercial cash-handling system could present real problems for the unbanked and otherwise vulnerable, sure. But cash is already an abstraction, albeit an analog one. It would be straightforward (in technical terms, if not political ones) to create the equivalent abstraction-processing infrastructure for digital abstractions.
The US cash-handling system amounts, essentially, to private banks working hand-in-glove with the Federal Reserve/US Mint to print, distribute, handle and collect paper bills and metal coins. A US-government-sanctioned blockchain, for example, could serve as the currency-processing infrastructure that supplants our current expensive[sup]1 2 3[/sup], theft-prone[sup]4[/sup], spoofable[sup]5[/sup] and sometimes violent[sup]6[/sup] cash-handling infrastructure.
Credit cards and cryptocurrency certainly have their flaws, but they’re not worse (and might be better) than the implicit burdens that come with cash. But again, both cash and all the newer systems are just abstractions that make it easier to exchange value with others.
It’s sort of like arguing over whether it’s better to read the news on newsprint or on one’s phone. Newsprint has undeniable charms, but the flexibility of electronic delivery has a charm all its own. But no matter the medium, the information conveyed is the same.
[sup]1[/sup] Ever get a quote for bank vault construction? Those things aren’t cheap!
[sup]2[/sup] In the US, at least, we pay a lot of people to handle cash: retail workers, tellers, armored car drivers and guards, mint employees, etc.
[sup]3[/sup] ATM fees can be punitive in the US. A nearby bank is on the site of my city’s nationally-famous farmer’s market, where a moderate-but-dwindling plurality of merchants only take cash. The fee to use that ATM is either $6 or $8. $4 is not that unusual elsewhere. Merchants who only take cash may not have to worry about arbitrary fees, but their customers sure do.
[sup]4[/sup] In an extraordinary coincidence, cash-only businesses are grossly overrepresented in among the ranks of those who underreport their earnings to the IRS. If these businesses paid taxes at the statutory rate, that rate could come down a bit for everyone.
[sup]5[/sup] Counterfeiting!
[sup]6[/sup] Assault during a mugging is not unusual in the US, and, though I have no cite, a small but countable number of people are killed each year ferrying cash to banks for small, cash-heavy businesses.