Nope I said developing world like Central and South America. Lots of tourists places will accept Euros and dollars as long as the bills are not damaged.

Mexico, Costa Rica, Panama, Nicaragua, Belize, and Colombia are places where I’ve done this personally and lots of Europeans were doing the same.

Friends and family in Costa Rica even advised that local currency wasn’t necessary and suggested bringing crisp bills from my bank.

Errr, you said "accepted everywhere".

But now that you point out "developing countries", that does seem more likely. :)

Ahhh, you've removed the "everywhere" term now. That should be clearer for people.

At least in Australia and the UK, if someone seriously tries paying with US currency they'll be laughed at right out of the shop.

Or at least nicely told to go and exchange it for real money (local currency) somewhere, then come back and try again. :)

I didnt realize the UK and Australia were developing countries but I guess post Brexit changed things.

Good point. Australia isn't, but yeah Brexit has kind of set the direction for the UK. ;)

Talking pragmatics, what are the chances any random coffee shop in the USA would take your money if all you got were $100 bills?

Aren't they legally required to do so?

No; I've been to places that just outright refuse to accept physical cash at all, and I live in America.

If you drink your coffee then pay, then yes, since you are now paying a debt and dollars are legal tender for all debts public and private.

If it's in advance of giving you your coffee, no, they could demand you pay in dogecoin only if they wish.

As a tourist maybe. But try to do it at any place mostly frequented locals in Europe and you will get nowhere. But funny thing. Same does not only apply to USD, but Euros as well. And EU doesn't even have army. And still on my last trip the taxis took the money.

What developing countries are in the EU?

I think the main disconnect is between developing countries (that may have currency stability issues and where folks are more likely to use dollars or euros) and the developed world, where there is no benefit in using USD for regular transactions. Plus a whiff of "F those Americans who act like they own the whole world".

And your specific comment that started this didn't read like you are only argued about developing world. My 2c.

At least in big cities in Argentina, you can pay with dollars in many places. Some shops like big supermarkets even have a sign that shows their exchange rate. (Note that the official exchange rate is AR$200, but the unofficial one is AR$400. You may get a bad exchange rate in some shops.) For buying clothes it may be more difficult because you must negotiate the exchange rate, and they may only accept only US$100 bills, and only if they look nice and is the new model that has a big face. It may be more difficult to pay the electricity bill in dollars.

(In small towns it may be more difficult, but not impossible, specially if you are nice.)

I am under the impression that pretty much anywhere in the developing world USD will spend. Maybe not in the west, but places that have a weak currency like africa, the middle east, and south america.

Here are a few cherry picked examples

https://www.reuters.com/world/americas/half-payments-caracas...

https://www.tripadvisor.com/ShowTopic-g293974-i368-k4798488-...

https://www.voanews.com/a/lebanon-leans-on-us-dollar-to-cope...

The Turkey example says dollars are not generally accepted, although they are easily changed.

And if there is a bank there you'll be able to convert your currency.

In most tourists locations yes (at a price, of course). But this is not at all what I was talking about.