Outside of these weird exceptions, it's SI all the way. And this doesn't really vary with age. The web site whrere you buy wheels and TVs doesn't know your age so it will say the rims or screens are 20" regardless of who you are.
It's even more pronounced with camera sensors, the size given in fractions of an inch is some kind of "equivalent to", whereas the size in mm is the actual size. Apparently the image sensor inch is 16mm or something like that.
Beaufort is a dimensionless label as far as I'm aware and grit is used as such too (i.e. it never says anything else than "240" i.e. it doesn't "240 grit" or "240 something per inch").
My list wasn't close to exhaustive. We use all kinds of weird units.
Besides bar I sometimes see mmHg for pressure. Shoe sizes. I've never seen acceleration in m/s2 outside a physics problem, otherwise it's either G or seconds to 100 km/hr.
I'm aware. But I'd say its mostly used as a dimensionless. When I argue "we use metric except for these few" I mean in the cases where the unit (a length, mass, pressure etc) is actually uttered or written.
In some cases as you note there are labels which have non-metric definitions underneath, such as sand paper particles having a never-pronounced inch definition. The same goes for some weapon calibers where you might say a ".303 cartrige" for rifle ammunition but you'd never say a ".303 inch cartidge". A lot of people probably use these labels without knowing they are using an imperial definition. And that (I'm guessing) is also part of why it survived the metrification.
> I've never seen acceleration in m/s2 outside a physics problem, otherwise it's either G or seconds to 100 km/hr.
"10s to 100km/h" is as metric as m/s2 though (But again not pure SI). g being a constant obviously has no explicit unit, it's as metric as you want it to be :) I hear "5g" as 5x9.82m/s2 but an american probably hears something else.
This is all as it should, however a large number of people have a really hard time groking the difference between kW and kWh.
So much so that I wonder if we should start specifying battery capacity in MJ to help people clarify things in their heads.