I manufactured plastic sheeting and all product was measured in inches, leading to a huge amount of conversion (24-3/8 sheet with +3/64 tolerance) and to me learning what a mil is (1/1000 of an inch). 10 mil plastic runs and stacks totally differently from 15 mil, and 40 and 60 mil take different amounts of time to cool and shrink, so there truly would have been switching costs going to meters (plus all the people who ordered 48x96 sheets, and rolls on 6-inch diameter cores, and so forth).
There's a lot of domain-specific units in use which aren't even imperial originally (fluid barrel, troy ounce/carat, ton of cooling, horsepower, AWG) that will stick around for a long time since they're used so frequently in finance, planning and B2B transactions, along with other imperial units that'll remain because they've taken on domain-specific uses (acre of land, fabric yard, bushel, mils) even when the engineers and logistics folks touching that same stuff are using SI equivalents.
