(Hey, Franklin, TN!)

Anyway, here's some more:

https://www.cashmatters.org/blog/paying-with-cash-costs-less...

"Key findings

"Cash payments are about 7 seconds faster than card payments with PIN entry.

"Cash payments are about 16 seconds faster than card payments with with signature.

"Cash payments up to €50 are cheaper, since the fixed costs for cash payments are on average lower."

https://www.researchgate.net/publication/321386231_Costs_and...

"The assertion that cash is inefficient is often based exclusively on cost considerations and a purely partial-analytical or business perspective (eg Bloching, 2007; Guibourg & Segendorf, 2007). Benefit aspects are not taken into consideration. Moreover, the empirical evidence is by no means clear-cut. Even in the more business-oriented approaches with regard to costs, cash payments are not necessarily more expensive than cashless alternatives. In Germany, the cost per transaction of cash is even lower than that of debit and credit cards. In terms of cost per turnover, debit cards are cheaper than cash, whereas credit cards are more expensive (Krueger & Seitz, 2014, Chapter 3; Thiele, 2016). In a study commissioned by the ECB covering several countries (Schmiedel et al, 2012), the findings did not reveal a uniform picture: in some countries, cash is the cheapest means of payment, whereas in other countries, cashless payment instruments are the cheapest."

https://www.researchgate.net/publication/265496400_The_Econo...

"We present three case studies that illustrate the welfare implications of substituting one kind of payment method for another. We find that when all key parties to a transaction are considered and benefits are added, cash and checks are more costly than many earlier studies suggest. In general, the shift toward a cashless society appears to be a beneficial one."

https://www.bundesbank.de/resource/blob/710096/4f27e9114ce3a...

[Ok, so I can't find a good summary quote. But it looks interesting. I think it's module 1 of the first link above.]