Imperial measurements are more /useful/ than metric, which is why the metric system is only used where governments force it upon their population.
The imperial system is broken up into units that are closest to what people find useful, instead of arbitrarily into tens.
Mathematically, Imperial is also generally superior, because it's mostly based on binary, like a computer, not units of ten, like a particularly stupid person trying to count on his fingers.
In other words, cups are broken into half, quarter, et cetera, and a pint is two cups, quart is two pints. The odds are that there's a unit right by where you need it, size-wise, instead of being forced to count large numbers of milliliters.
Even for conversion, normal people are better off with Imperial: You have a recipe, and want to increase it by fifty percent...so you can either turn one cup into 1 1/2 cups, or you can turn 237 milliliters into...umm...355.5 milliliters.
Only bureaucrats, who are endlessly converting huge numbers in order to calculate how to force us to do things, and scientists/engineers, who these days are often glorified bureaucrats anyway, actually need to convert one kind of unit to another, like kilometers to meters, or centimeters (length) to liters (volume).
Real people rarely, if ever, need to convert one kind of unit to another. So metric is nothing but inconvenient, to them.
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