Yes, the $3/night is some sort of convention center tax. Priceline does cover this in their fine print, but one of the problems of Priceline generally is that you never know till you arrive what the add-ons are actually going to be and, even worse, there seems to be some inconsistency among hotels in the same area about what's included and what's not. Also, when I arrived, the hotel didn't have any record of me from Priceline and the matter didn't get sorted out till the next day -- who screwed up isn't clear, of course. Had to wonder what happens when an airline has no record from Priceline and you don't have a day to sort things out. That said, my room was great value, the breakfast was ample, and the front desk was friendly, so I was pretty satisfied.