(Or how 3 pounds became 30.5 oz.)
Once upon a time, long long ago, coffee was sold in 3 pound cans. This coffee was roasted and ground, ready for use in office coffee pots and home percolators. The cans were cans, tin cans, cans which once emptied found many uses around the home. Coffee, being a storable agricultural commodity, was always subject to volatility in supply and so in price, despite the
international cartel the supply management setup known as the
International Coffee Agreement. IIRC prices for 3 pounds of coffee ran around $3 in the early 70's.
As time went by, consumer prices for coffee increased and coffee roasters found resistance to paying the high prices. So someone had the bright idea, instead of raising the price as we need to, let's reduce the amount of coffee in the can by a bit--same effect but consumers will be less upset. (This was probably the same someone who about the same time reduced the amount of candy in candy bars.) And the someone was right.
I don't know when flaked coffee was invented--there's a patent from 1991--but it was touted as a big innovation, delivering better taste for the coffee drinker. The thing about flaking is it means an increase in the volume of roasted coffee for the same weight. Consumers lapped up flaked coffee.
Bottomline: between reducing the amount of coffee in a can and increasing the volume by flaking, the current Safeway "3 lb" can of coffee contains 30.5 oz, or just under two pounds. And when you open the can, as I did yesterday, you find it's only about 3/4 full.
So ever since the first decision to reduce the weight without changing the size of the contained, Safeway has been shipping canned air from its warehouses to its stores, wasting space in its trucks.
(I should note that Folgers, and I assume other roasters, somewhat reduced the size of their containers when they switched from tin cans to plastic containers for their coffee.)