To answer your question ... You'll be quoted in US dollars ... but, know the exchange rate ... as you'll most likely get J's in return
As well some places have higher & lower exchange rates..beach vs. westend / one bar vs. another
prices for drinks & meals are quoted in US .. @ most places
I personally "get a kick "out of seeing all those 500 & 1000 dollar bills ..
No stress, spend your US or J's as you please
Have fun !!