When buying canned pet food, have you checked the price per can? Don't be surprised when those super large cases of pet food are actually more expensive than the smaller cases. Because the smaller ones are bought more frequently, the store may get a better deal on the smaller cases, meaning the price per can might be cheaper with the smaller case than when you buy more.
Some stores also make it confusing to determine the actual price per can or per pound, so make sure you carry a calculator, or use the calculator function on your smart phone, to work out the actual prices. This way you can make sure if that bulk buy of dog or cat food really is the deal you think it is.