We all learnt to measure in metres & cm's at school and then went out to buy houses which were measured in feet and inches!
A similar thing happened in the US.. there was a big push when I was in grade school to get the kids to understand metric because we were surely going to switch over soon. So, I learned all of that stuff and ignored all the pint/quart/cup stuff. I still don't really know those units.
I've been exposed to most metric units through jobs or hobbies over the years so I can convert reasonably well. Celcius could take me a while. I know -40=-40 (good for telling stories of Winter in Montana) and 0=32 but I can't do anything else in my head yet.
Sounds like I should count on using metric when I can.