That explanation leaves out the main reason the delivery by milkman declined. The milkman was usually more convenient, as the milk would be on the doorstep bef

That explanation leaves out the main reason the delivery by milkman declined. The milkman was usually more convenient, as the milk would be on the doorstep before you woke. Many delivered eggs, cream, orange juice, and cheese as well. The supermarkets started stocking milk - initially in the same crates and glass one pint bottles as the milk man would supply, and sold it for an uneconomic huge loss. It wasn't uncommon for the same milk, from the same dairy and bottler to be half the price in the supermarket. Even while the guaranteed minimum wholesale price of the milk marketing board remained. You were even expected to rinse and return the bottles to the supermarkets. Cartons came later, but not too long after. Larger sizes like 4 pint plastic later still. Customer loyalty couldn't last, though it took a surprisingly long time under such pressure for them to die out. In UK supermarkets the price of milk is still held artificially low by all of them as dairy farmers go bankrupt. It might be the only item where Tesco and Sainsbury match price with Aldi and Lidl.