Cash based commerce should just be rounded to the 1/10th dollar not the 1/100th dollar; there's just no need for such precision.
I'd just announce that while still legal tender, the penny, nickle, and quarter won't be minted any longer except in low volumes for collectors, and that cash transactions may be rounded down to the nearest 10th dollar if proper change is not available.
IE a cup of coffee costing $4.17 would cost $4.10 if paying cash. I suspect vendors would just update the cost of everything to land on the 1/10th increment.
I guess you may need to worry about people playing arbitrage games with metered things like gasoline, but even there it's probably just a marginal problem.
Dime is a weird word; it doesn't convey that it's a tenth of a dollar, does it?
[edited to add examples and digression on gasoline]
There were also jokes about buying one grape at a time so the whole bag got rounded to 0, but I worked at a grocery store for two years and never saw anyone try to exploit the rounding, even to a lesser extent :)
Imagine you own a gas station. Your actual cost to fill your tanks is some multiple of the price you can charge per gallon. Requiring 10 cent-rounded prices kneecaps your ability to efficiently price your product.
Flipping it around, if you think $1/10 increments are good enough for a gas station owner, why aren’t they good enough for Microsoft when its shares are traded? Decimalization in equity markets has been widely seen as a success because more precise prices communicate information about the relative interests of buyers and sellers more accurately.
Given the predominance of digital transactions, it’s hard to argue that the transactional efficiency gains of less precise prices are worth the downsides.
This is… already the situation?
Most gas stations where I am are pricing their product in thousands of a cent and rounding the total off to the nearest cent when it’s time to pay.
We got rid of the penny a decade ago in Canada. It just means that for cash transactions the gas station rounds off to the nearest five cents instead. The most they can “lose” is two cents _on the total transaction_. Hardly seems different than losing several tenths of a cent on some transactions (as they already were) in aggregate.
We could as easily add a 1/1000th unit to the dollar, and mandate that for cash transactions round to the 1/10th but for credit and other electronic transactions they'd be to the "iota" or some other charming term for the millidollar. I'm pretty sure that aeons ago there were half pennies, so it isn't completely absurd.
Also, I'm pretty sure that in the not so distant past stocks used some weird fraction of dollars not decimals[1].
[1] https://www.investopedia.com/ask/answers/why-nyse-switch-fra...
[edited to add example of fractionally denominated stock prices]
[edit2: ah, sorry you mentioned the fractional stock issue with the observation "precise values are good" which they are. I still retain my position that, for retail cash based commerce, precise values are less valuable than the time invested in the transaction. ]
