The Metric system is based on.....GASP ... Science!
The reason that the metric sizes are seemingly odd, is that they took the existing sizes, and made the change in measurement systems, not adjusting sizes.
Besides, who asks for 12 oz or 341 ml of pop? Nobody, they ask for a bottle/can of pop.
Nobody wants to change? Wow what a broad statement! The US is one of the only countries not using the Metric system. Do you realize how subjective the Imperial systems was? The King would have his foot measured to define length of "foot". Imagine a small king, or a large king, and the anomalies of the changes. Luckily, the standards stuck for the current Imperial system. Funny...the US hanging onto something developed by another country! You mention "10 Americans....", but there are far more who would not want the Imperial system to return.
Change in general is a part of life. I was a young lad when Canada changed to the Metric system, and while it took time to understand, I managed. I suggest the fear of change is greater than the impact of change - at least in this case.
