I used the Steven Wright (comedian) imperial hybrid for my height (5" 17" lol). My 10 year old kids say 4 feet whatever for their height, although they probably know it in cm as well. My son will usually measure something out in inches, but I think that has as much to do with his handyman grandfather working with him in building things.
In looking through the grocery flyers, most produce and meat is advertised by the pound with metric either in smaller print or not at all. Car ads still use mpg in bigger font with l/100km in smaller print, if at all.