A foot divided by 10 is 1200thou. The nice thing about Imperial is that you can mix bases. And no, dividing by a multiple of 3 is not a "contrived example", it's literally the second prime. A multiple of 3 is by definition more common than a multiple of 10.

You know what also doesn't make sense? The SI Prefix system, where you have redundancies like "A thousand megawatts" instead of just saying "A billion watts". Most languages already have built in prefix systems. In fact, South and East Asian languages space theirs every 10^4 instead of 10^3, making SI prefixes a clusterfuck to use. That's in addition to the fact that the prefixes themselves are chosen haphazardly. The ordering of Micro, Nano, and Pico has no discernible pattern as most people simply know all three words to mean small. Abbreviations such as M, m, and μ, are easily mixed up.

Contrast that to thou and mil, which are easily remembered as abbreviations of thousandth and millionth. It's also easily extendable to an arbitrary precision.

IMO there is no question about metric system's usefulness especially because our counting system is in base-10. Metric system is tailored to that, whereas US ANSI system is tailored for base-12, which is the wrong base to work in.