This is neither the first nor the last time a hotel will quote rates in USD or EUR and then convert to local currency when charging the credit card of the guest (partly also because the hotel can't charge in other currencies than their own). This is so common that I would say it is close to being the norm when you are dealing with hotels with rates in other currencies than their own, e.g. try traveling in Turkey where many properties will quote in EUR (to protect the revenue from TRY fluctuations) - but maybe not so extreme as in the example of the OP.

Actually, you will loose twice by this. First when the hotel converts the rate to their own currency (applying their own unfavorable currency exchange rates) and again when the your bank/credit card converts the foreign amount into your currency. That is how a rate quoted in EUR or USD often will end up with actually being the EUR/USD amount +10% when the charge shows up in your credit card statement.

Expecting that your card will be charged an amount similar to the rate quoted when the booking is made, is bound to fail - regretably but this is the reality,