What's special in the rest of the world isn't just a metric system, it is one particular metric system: the SI system (also sometimes called the MKS system, for meter-kilogram-second). The SI system guarantees not only that we have nice multiples of powers of ten, but also that all scientific units are easily convertible to each other. This, for example, enables the fact that one ohm times one farad is exactly one second! That's why, for instance, you may have heard that NASA (or most any other scientific org in America) uses the so-called "metric system", again specifically meaning SI units. (There does in fact exist an arcane scientific system based on the foot-pound-second, but nobody - not even Americans - uses it.)