Base 12 works better than base 10 for doing simple fractions. since 12 is divisible by 1,2,3,4,6 and 10 is divisible by 1,2,5. Every time you measure something in metric that isn't exactly half you end up with decimal point strangeness. Measuring a yard of fabric into 6 pieces is 6, 6 inch pieces. In the metric world you have 6, 16.6666...cm pieces.
Also 1 foot is a very usable length, there is too much of a gap between meter and centimeter, do metric countries even use the decimeter? Would you describe me (6'4") as 19.4 decimeters tall?