Are metric measurements like decameters and hectometers ever used?

I'm American, but follow mostly Europeans and Canadians online and use metrics in my own head just because it makes more sense.

I gather that the deca-/deka- and hecto- (along with a few other) prefixes are similar to imperial furlongs, leagues, stones, barrels, kegs, and hogsheads: They exist, but no one uses them outside of very specialized circumstances.