As we said, it all comes down to what you're going to use -- and what you have room to store. That 16-roll pack of paper towels isn't a good deal if you don't have anywhere to put it. Pay a little more for a three-pack that'll actually fit in your pantry.
Frozen foods are another area where would-be bulk buyers can get more than they bargained for. You'll squander your savings pretty quickly on a gigantic bag of frozen chicken that won't fit in your freezer. Remember, a good deal isn't a truly good deal unless you actually use the things you buy.