We try not to. Too many foreign guests who don't understand it. The only one that we repeatedly use is CAD USD, GBP and EUR which are the currencies we generally deal with. I find that some Americans don't understands USD so I sometimes use US$, even thought USD is the international currency code for the US Dollar. Everyone else is used to deal with multiple currencies, so we've seen the three letter abbrevations for currency code all over the place.
I can't manage to get my PC to write the two different currency symbols for dollar. The CAD is a $ with a single line and the USD is a $ with a double line. But that would be even more confusing.
There is also this nonsense with our provincial code. The two letter code for the province is currently QC but it used to be PQ but we still sometimes see QU instead. The three letter is easy, it's Que..
We stopped using the double line dollar sign a long time ago. No one should be confused by seeing a single line dollar sign. I will use 'USD' when quoting prices to guests in other countries.
I think what you consistently forget is that Americans do not travel as much as other nationalities do. Therefore, they never see their currency written as 'USD'. There is no need to use it in country. Most of us know it because we have to. I tend to collect odd bits of information (some would say trivia), but it's not a wide-spread activity to know the currency symbols for many countries unless you have a need to know them.
Look how many people can't keep track of who's playing in the Olympics because flags are used to denote the country. (Altho, I will proudly say that my 4 yo grandson can name almost every country in the world by its flag and point it out on a map, but again, there's that trivia gene coming out.)
I'd hazard a guess you could find a few innkeepers in the US who do not know all of the postal abbreviations for the states and some who don't know all the states written out in full.
I've seen PQ and QC and Que come thru on reservation requests where the guests give me their info in an email. I roll with it. My program has QC so that's what they get back.
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Oh, I realize that. I deal with it all the time. I haven't yet had a European ask me if they can pay in Euros in the stores. Not an Aussie ask me to pay in AUD and not a Brit ask me if they can pay in GBP. Yet when I mention to Americans that USD is not legal tender in Canada they look at me like I'm from outer space.
Thing is, most businesses will accept USD around here, but the exchange rate sucks. The worst part, the more they deal with Americans, the more abusive they seem. The exchange rate at places like fast food chains is sometimes just abusive.
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I will hazard a guess why they might ask that/think that. The couple of places I have been out of the country that were 'nearby' WANTED American dollars. You paid in USD and you got back the local money. So, all prices in local money, but they wanted you to pay that number in USD. Essentially paying a substantially higher amount than a local would pay.
So, the places Americans go (the Caribbean) have trained them that foreign countries accept USD. Gladly. Many places didn't want me to pay in local money. They kept pushing it away saying the prices were in USD, I had to pay in USD. My guess is they did that to all customers no matter what country. Expecting payment in the more valuable currency.
Americans don't expect to use USD in Europe. But I bet no one in Mexico turns down USD for payment. So, you see where the disconnect comes in. Most Americans don't go to Europe, they stay closer to home. After all, most of us traveled a long way to get here in the first place.
We use CA coins here on an equal footing. Not dollars, but coins no one bothers with. Here. Heaven help me if I go out of northern New England. You'd think I was some sort of career criminal the way I've been treated for giving a clerk a CA quarter.
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