mpg vs fuel consumption

[Ol'Man Driver]

For those of us who are lucky enough to live in the metric world, it is easy to calculate costs based on the fuel consumption. We specify the consumption in l/100 km. If the gauge shows 1 liter more or less per 100 km, then 100 km cost 1 liter more or less.

Very simple.

But what does it mean for my fuel consumption when the gauge shows 10 mpg more or less? That depends on.
40 mpg instead of 30 mpg mean 25 gallons instead of 33 gallons per 1000 miles, thus saving 8 gallons,
50 mpg instead of 40 mpg mean 20 gallons instead of 25 gallons per 1000 miles, thus saving only 5 gallons.

How can you US guys live with this?
How would you comment on this article in ScienceDaily?

[wicked1]

We US guys have to live w/ a bunch of crud that doesn't make much sense.

I'd love for the standard to change, as it does make more sense the other way.