Thanks Marc for the information. I've pre-paid the Ritz-Carlton in Santiago through the tour company I'm using and I paid in US funds so I'll have to check the invoice to see if it included the tax. However, most hotels do usually add the tax on later once you get there even if the room has been pre-paid so at least I'll have this information handy if it comes up upon check-in or check-out. I'm assuming of course that it won't matter that I'm a Canadian paying in US funds versus an American paying in US funds for the hotel tax to be not levied but it could be just for you, US citizens.
Pat