Why kms?

[figbat]

Funny thing about buying liquids isn't it. Milk and beer still commonly traded in pints while nearly all other consumable liquids are sold in millilitres or litres.
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The pint is an oddity, but the mile is still the official unit. If pubs stopped selling beer in pints and changed to half and quarter litres I bet 'the pint' as a unit of liquid would quite rapidly fall out of use.

The Weights and Measures Act still allows for beer and milk to be sold in pints, so it is still an “official” unit. Pretty much all other items must be sold in metric, by law.