Piffle. The notion that a preference for the "Imperial" system indicates a love for freedom and dignity is quaint, but unconvincing. Feet and inches are used to measure lengths, not human dignity.
Traditional systems of measurement may be good for carpenters—who are not known these days for great precision in their work—but it can be hell on anyone trying to build or maintain modern technology.
I am an engineering professor. My students must know unit conversions. It complicates their work to have to convert between traditional systems of units and the International (SI) units. What is worse, the traditional units introduce ambiguity and therefore the danger of errors.
The other day, I asked my class to define ton. They replied that a ton is equal to 2000 pounds. But that is true of a short ton. A long ton can be 2200 pounds or 2240 pounds. A freight or measurement ton is 40 cubic feet. A ton of refrigeration is 12,000 BTU/hour. (I am not sure which definition of BTU is used—there are several.)
I am not in favor of forcing people to drop familiar units of measurement: miles are fine for measuring driving distance; pints are OK for dispensing milk; yards are just right in football. But serious work in science, engineering, or commerce requires more carefully defined measurements; ambiguity and imprecision are not good.
You left off a couple dozen more tons. Tons of tons one might say...
The Metric System has a place in technical areas, perhaps, but I have been working in Engineering for the last twenty years, and we've been getting along just fine with the old units. You know which ton you are using because of the context. If I am buying gravel, it's 2000 pounds. If I am buying an air conditioner, it's 12,000 BTUH. If I am buying a large refrigeration plant from an old-timer, it might be 144,000 BTUH, so it is best to ask.
Traditional systems evolve. New systems are imposed. Social evolution is respectful of the humans who make up the society. There is no need for respect of the individual in a system that is imposed.
And, of course, the traditional system relies on the human ability to divide things into halves and thirds. Ask any five-year-old child to divide a line into halves and thirds, and he will get it right to within 5% or so. Ask an adult to draw a mark indicating a tenth, and they will be all over the board.
Metric units are supposed to “tie down” to natural constants, such as a liter of water weighing a kilogram.
What’s the natural component of a meter? I like both systems - metric for volume, English for distance. The marketplace is slowly adapting to both, as well. No one objects to a 2-liter bottle of soda in the US, for instance.