Centrally located next to The Shoppes at the Palazzo. Huge store, with great selection. But, the prices are definitely pricey--at least for food they are. If you have time and want to save your money for Vegas venues, trot on over to the CVS on the opposite side of the street. The prices are much more reasonable and will save you a few bucks. It'll take you 10 minutes to get there, though. Not enough pedestrian crosswalks, grrr!
Grabbed a Rockstar Punched at $2.99 for my friend. The checkout line was crowded, but cashiers were fast and the line moved quickly. I appreciated the single line system, rather than the chaotic one-line-per-stand system at CVS. But by the time I had finished grocery shopping, my friends over at Earl of Sandwich had already left for the hotel. Too slow :c