Try 45 and counting...

Yes and no. Americans basically use both systems, some more than others, whichever is more practical for a certain situation. Wine and drugs come in metric amounts, for example. Many of us shot or still shoot 35 mm photographs, 8 mm movies, and 9 mm ammunition. I could go on and on. My favorite example is Puerto Rico, where most of the roads have distance markers ever 100 meters, distance signs are In kilometers, and speed limits are in miles per hour. Let’s not forget the metric automobile wheel sizes that the whole world uses and that have diameters in inches. People from countries that only use metric may make fun of mixed use in the US and UK, but they miss out on practicality and understanding.