Why is Coca-Cola sold by liters and not gallons?

Answer 1

The gallon we use for our liquids comes from the Roman word galeta, which meant "a pailful." There have been a number of very different gallon units over the years, but the gallon we use in the United States is probably based on what was once known as the "wine gallon" or Queen Anne's gallon, which was named for the reigning monarch when it was standardized in 1707. The wine gallon corresponded to a vessel that was designed to hold exactly eight troy pounds of wine.

Answer 2

I buy both by the litre, it being the simpler and easier unit to use. Some people buy both by the gallon. Others buy cola by the gallom and milk by the litre.

Answer 3

Because all the carbonation would EXPLODE in the gallon bottle!