If you're new to shopping around...
1 - Do some comparison shopping first. Learn where the best deals are for various foods.
2 - Bring your calculator (or use the one on your phone). I calculate price per pound on everything I buy so that I can do a proper apples-to-apples comparison.
3 - If you find a great deal at a store, don't buy it unless you need it. I found ground lamb for a great price but I don't feed hot proteins in the summer. I could buy now and save for the winter, but then I'd be taking up freezer space - the lamb will be there in November.
4 - Go early. The parking lots at these places fill up. The US Foods parking lot is the size of a postage stamp and cars were waiting in line to park.
5 - Not sure if your dog can or will eat a protein? Buy one and see. So much better than buying a case only to find out
your dog has a sensitivity.