>Explain the 200 cars stuck for two days on Haldon Hill and 250 on the Okehamton bypass in snowy conditions
I doubt any were fitted with snow/winter tyres, which are constructed differently from ordinary tyres. Any vehicles in your area fitted with snow/winter tyres were the ones not stuck on Haldon Hill and the Okehampton bypass but were where the drivers wanted to be (home, work, etc.).
As I say, from personal first-hand experience, Scotland, northern and eastern European countries aren't supplied with vehicles with different-size wheels and/or tyres from those in your area; in fact, the numpties around Edinburgh and Glasgow who don't fit their vehicles with snow/winter tyres get the same stuck as the drivers of the 200/250 cars stuck on Haldon Hill and the Okehampton bypass.