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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