One way to save money is to make your own convenience items. One idea is to buy chips, crackers and other items in a larger quantity and package in smaller snack size storage bags. It may be considerably cheaper to do this than to buy the products already in snack sizes.
Another idea is to make our own oatmeal packets. By making your own you can save money and you can make the flavors you want. If you buy variety packs you may get flavors that you don't necessarily like. Also, you know the ingredients that are in the homemade packets. If you won't be using them fairly quickly you can keep them in the freezer to keep them fresh. I have also heard of people storing the used bags in the freezer until they make another batch.
By searching online you can find several recipes for making your own convenience items.