The UK is very much a mixed country, they still use imperial on large distances, weights and all that, but have been changing very much to metric in more precise things like small measurements. Here in Spain we use inches still, but for very specific things like in plumbing, where if you say the measurement in metric it's a socket, and in inches it's a thread
Besides you Americans generally use metric in more scientific things like forensics, medicine, technology studies and scientific measures for example, so you are slowly being assimilated muahahahahah!!! And on this notion, seeing as aeromodelism involves more engineering that cookery, well... but then now we're at it, maybe we should do away with both of them and use the aeronautical measurements, which are really a bit of both, and adding a bit of their own, like knots.
I think to be fair, seeing as the show is international and reaching out every time more worldwide, it should be subbed with the measurements in both, although I do understand it would be more work, but not that much really. A lot of the world doesn't speak english (yes, there are other languages!!) and those people are already putting a lot of dedication into following the show in a language they don't know too well at all, and the subtitles in both systems would help make things a lot easier for those people too, as it's one thing less to think about when they are franticly trying to translate in their heads.
As far as temperature is concerned, when I hear that the weather is in the high 70's for example, the only thing I can think of is "Give Hades my regards!!". Ok, so freezing is 32º and boiling is 212º... can someone please tell me where those totally random numbers come from? Might as well use kelvin, at least it's a logical system that even runs parallel with centigrade (centi, as in a round number like 100) and just redefines the "starting point"!!
Let's put it this way, it's a man's world, and men were put in charge of it all... now if you had "founding mothers" instead, it would be a lot better, like "12 seeds make a flower and 20 flowers make a flowerbed"... we almost got it in the 60's, but... damn imperialists!!!