The big advantage is avoiding costly errors. An airliner crashed because the fuelers mixed up pounds with liters. The space telescope didn't work properly, because somebody mixed up inches and centimeters.
Get with the program folks, metric is much easier to use than that old system - and its fun and you're already using it for your money... :))
Americans are slowly going for the metric system, but ever so slowly. 5k races, a two liter of pop, and 9mm ammo are much the norm. But water still freezes at 32 degrees, gas sells by the gallon, and beer comes in 12oz cans.
I asked a similar question to this some weeks ago. It's amazing that a country as technologically advanced as the US is still stuck in the Middle Ages when it comes to weights and measures.
Rather comically, when I was introduced to elementary decimals as a small boy, in 1946, my schoolteacher tried to create some interest by calling it "American arithmetic". (a reference to your decimal currency) and explained how much easier it was.
As one that worked in the scientific community for several years . I always have felt that the metric system is easy and practical to use. When Carter was president , the US was supposed to be on a. 10 year plan to convert, but there was so much resistance that it fizzled. If you really dig into it, metric makes a lot more sense .