I think mdosu is partially correct. Most countries have already converted to metric, but the US hasn't converted yet.
The US, however, has committed to convert in a loosely open time frame. That's why in the US all containers/packages have to have the metric measurement in addition to the local imperial measures - check and you will find. The same happens to the speedometer in all cars in the US.
I assume all cars in the US have both, but I have been driving only BMWs since 2007, so can't confirm, but I am sure many forum members can.
Converted countries don't need anything other than metric. I wonder what does it look like in the UK.
Royale with cheese anyone?
Now: 2013 SG ZCP E92 M3; 2011 DSB X5d
Before: 2011 JZB E93 M3; 2008 Monaco Blue E90 328i; 2002 E46 Steel Blue 325i