One of the easiest travel tips to save money is to simply take a walk around your hotel after you arrive. Look for drug stores, food stores, convenience stores. A 5 – 15 minute walk could save you a lot of cash for things like water, snacks and wine (which always cost more at hotel gift shops).
In my case, on my recent trip to Las Vegas I just had to look out my hotel room at the Encore to see a Walgreens close by. Walgreens has everything, and I went a couple of times for cheap lunches and cheaper wine than I could buy at the hotel.