"feel free to tell us why we're dumb for not using the metric system."

Since you asked, there's 2 issues:

1. Everyone in the world buys and sells in metric, and then has to convert for the USA, we even screwed up the International Space Station!

2. Metric is base 10, conversion just require moving the decimal point, USC is insane with 3 hands to a foot, 3 feet to a yard, 22 yards to a chain, 10 chains in a furlong, and 8 furlongs in a mile. What is that?