It's a free country, you can use ; pecks , bushels, chains and furlongs if you want.
By law (for now), trade has to be conducted in metric. Weighbridge tally rolls (now replaced by electronic versions) must also record in metric.
Scales used for trade must be type-approved for trade, and that means able to display in metric. If they can display in any other system - fine, no problem, knock yourself out. But the sale must be in metric.
When I worked in metrology, we had a little private museum on site (had some 5,000 year old merchants scales from Egypt). They had example scales from the 60s that were marked n metric and imperial. Meaning the "metric martyrs" up in Sunderland must have really dug through the scrap heaps to find imperial only scales. And one of the selling points of the first electronic scales was the ability to display in metric or imperial at the flick of a switch.
Apparently metric was added in the 60s as European imports started - which were of course all measure in metric. Much easier to split 1kg into 8 125g packs if you have metric markings. rather than risk the 8x"nearly"4oz packs.
At the end of the day, all the love for imperial is for the cuddly everyday units that chocolate is measured in (which might explain a lot). If you burrow through your "Imperial in 999 easy steps" book, you'll see there are quite a few units that are never coming back. BTUs spring to mind.
And for obvious reasons, you aren't going to find a single petrol station that is ever going to want to go back to £/gallons ....
HOW MUCH ?!?!