Watered-Down Milk
I had a friend whose parents would buy a gallon of whole milk and pour half the gallon in another jug, then mix water into both to dilute it. She always just thought that other people got a different brand of milk because drinking milk at a friend’s house always tasted different. Her grandparents did it too. Really weirded me out when I saw her mom just pour milk into an empty jug, and mixing water with it.
I 100% guarantee you that their grandparents learned that in the great depression.
Story credit: Reddit / Tibbersbear