Since I first heard of feet and inches, I’m asking myself, why anyone would use them. No, “Because that’s what we’ve always been using” is not a satisfying answer.
When I went to school I learned the metric system. I instantly liked it. It was a logical, intuitive and elegant.
Of course I’ve had heard of miles, gallons and the like, but when, years later, an exchange student asked me how far it is to the next city, I had a problem. I remembered that 1 mile is about 1,6 kilometers, but what about the rest? It was 5 km, so I said “It’s about 3 miles and… Yeah, about 3 miles.” Giving such an inaccurate answer was as ungerman as it gets.
We all use the decimal numeral system. It’s based on the number 10. That’s what makes it simple. Why don’t you apply the same principle to you units? There’s no need for a base of 3, 4, 6, 12, 42.
I know that there are a lot of Americans who spend their time reenacting civil war battles, so I shouldn’t be surprised that you like to play medieval Europe when measuring distances.
But seriously, don’t you think that it’s time you, Liberia and Myanmar join the rest of the world? We live in a modern world with a global economy. Hop on the boat.