I'm an American that grew up during the time they "tried" to go metric and none of this surprises me. Volumes are tricky for me, but I have no problem going from imperial to metric. Most other countries see the US and are like, "why aren't you using metric?" and we're like, "what's in it for us?" We learned metric in school and it's great, for exact measurements. Sometimes you just want to use what you have and not think about it. I don't know what 310mL is, I know how to measure 2 cups of water with...2 cups of water.

Speaking of globalization, TVs are still sold and classified in inches :-)