There are certain things we take for granted when it comes to product sizes: a carton of eggs will have a dozen eggs; milk comes in quarts, half gallons, and gallons; and margarine and butter are sold by the pound.
Cross off margarine from that list. These two “3 pound” tubs of Country Crock margarine look identical:

However, checking the net weight statement reveals a surprise.
*MOUSE PRINT:

The three pound tub is now three ounces short. Mouse Print* asked the company why they downsized the product. They replied:
Unilever Foods takes great pride in offering the highest quality products at reasonable and fair prices, and we apologize for the inconvenience our recent packaging change has caused.
In order to maintain price, we have reduced the size of the container for several reasons:
– Increased costs of raw materials, including ingredients and packaging materials
– Transition to Trans Fat Free products
– Tamper resistant containers[In a separate letter, the company added:] A redesign of the product line was undertaken which involved packaging changes that had an impact on the net fill weight of the products. Prior to implementation, the changes were thoroughly tested with consumers to ensure optimal consumer satisfaction.
Of course, I am sure consumers applauded the company for removing three ounces from the container and not calling that fact to their attention. This is how some sneaky manufacturers opt to pass on a hidden price increase by just shrinking the product a little, and keeping the price same.

What could be a more common home improvement purchase than buying a gallon of paint? You may fuss over the brand, the color, and the luster but you certainly don’t pay attention to the net contents statement on the can. Why should you, after all? A a gallon is a gallon.