It's absolutely stupid. Moreso because they teach pretty much only metric in american schools. So you basically have a large group of people that know metric, but everything is in standard, and they don't really know standard that well. I have to constantly remember a measurement system that isn't easily in base 10. Like I can easily tell you both boiling point and freezing in Celsius but I couldn't tell you the Fahrenheit that water boils to save my life.
Plus when i went overseas I had to constantly do conversions in my head.