A purchase package can be convenient per unit and leave unused material. The assessment should know the relationship between format, frequency of use and storage possibilities. The cost of the material really used can be different from the one suggested by the price of the whole package.
I propose to observe how much is used and how much remains without a concrete destination. The storage conditions require appropriate indications to the product. A smaller format may cost more per unit and be relevant to a limited demand, but the comparison needs to be verified.
We imagine a material purchased for occasional activities. A large package can cross many months before it is consumed. If part is no longer usable, reading must include this loss along with the benefit gained at the time of purchase.
Proof of a different format should compare usage, expense, and frequency of deliveries. Any environmental effects require a wider perimeter. The format becomes a conscious choice when it is linked to actual consumption and the conditions that allow the material purchased to be used.