The metric system is the last surviving relic of an attempt by the french to "fix" problems caused by the ancien régime. Though the other two things (the ten-hour day composed of 100 minutes in an hour and the French Republican Calendar) were stunning failures, the metric system, despite the fact that it was completely ready to be a failure, survived.
Whereas our (hereby referred to as "real") measurements came about through evolution by human usage (a foot's roughly the length of a foot, hand a hand, inch a thumb, etc.) the metric system was totally pulled out of someone's *** (one ten-millionth of the earth's meridian? What the ****?)
The metric system makes sense on paper. On paper, communism makes sense. A new unit isn't needed every ten, hundred, or thousand times that unit is repeated. It maybe needed more often, or not as often. That is the beauty of the real system. Humans were able to pick base units that made sense, and new units came about when necessary, capitalism at work! The metric system has always been bureaucratic ("It works because the nouveau régime will guillotine you if you say it doesn't!"), and the fact that the rest of the world uses it is not an argument in its favor. In fact, that argument is a logical fallacy called "argumentum ad populum". Look it up.
The metric system has only easily been put in place in places where the people are ignorant and illiterate (India, Iraq, 19-century Europe, etc.). In places with high literacy, the change has been nearly impossible (Canada, Japan, UK). Japan's system of measurement, though different from ours, came about the same way. It took Japan 42 years to convert before the system was outlawed, and even now, 40 years after the old system was outlawed (in 1966), the old measurements are still used commonly in agriculture, architecture, and cooking.
Bottom line. I hate it. I will not use it. I will not conform.