I can buy two gallons of milk at Costco for the price of one gallon at my local store. But I don't buy from Costco because the second gallon always goes bad and I throw it out. Throwing out food feels bad.
Anyway, what do I care about the "free" second gallon if I don't actually drink it?
Edit: hey look, a study:
> A series of experiments demonstrates that consumers exhibit aversion to waste during forward-looking purchase. These experiments further reveal that such behavior is driven by distaste for unused utility, a reaction that is shown to be distinct from an aversion to squandering money. Waste aversion is especially pronounced when consumers anticipate future consequences and deprivation is salient. In addition to demonstrating robustness across consumers and marketing contexts, the results also demonstrate how waste aversion can lead to self-defeating behavior in which consumers forego desired utility.
http://www.sciencedirect.com/science/article/pii/S1057740811...