In the 70's they vainly tried to convert everything to metric, all at once, and ditch the Imperial system all together. It failed for the most part. The biggest example of the failure was when they tried to sell gas by the liter, rather than gallon. I think that lasted around 2 weeks before the resultant public uproar caused the government to ditch that idea. Sure, we sell soda by the liters these days, but ounces is the go to mindset for Americans. Sure, metric converts very easily, just move a decimal point. But it isn't so hard to memorize the English conversion formulas for everyday things. Sure, if you're a scientist or doctor, it makes sense to keep it simple and quick with less chance for error.
@@SELFENGINEER I tend to think it's from Asia, as ships need to carry freshwater. Larger barrel would be more efficient. Coincidentally one ton of water was close to one cubic meter in volume. I know that one meter is defined by fraction of earth circumference by the French, but still, what a coincidence.