I don't think you're being obtuse Mick, I just don't think that you totally appreciate their value.
Prior to being converted, I too was sceptical about their efficiency or thought that there really was no need, that there was no requirement for their use in the UK and it was probably all a bit of a waste of money etc. However, where I live now, we've had snow four out of the last 5 winters and when we get it, it tends to cause chaos.....for the folks who don't have winter tyres on their vehicles, which boil down to the vast majority. People running around with 3 or 4mm of tread on summer tyres with zero grip on hills, sliding backward and slewing into parked cars. We have a particularly long steep hill up into our village, a main road. Once there's a couple of inches of snow on it, it's hell. It would be funny if it wasn't so serious, but I've been happily able to drive up it in my Saab 9-3 1.9, safe and with plenty of grip, only to be passed by cars sliding backward down the hill (I've had to overtake them to avoid a collision) and I've made my way merrily to the top!
For general winter use, I wouldn't go back to using summer rated tyres again in my part of the world. If I lived in the South West, I definitely wouldn't bother, but with average daily temperatures where I am that consistanly hang around the freezing to 3 degrees Celcius mark on most winter mornings, winter tyres have saved our backsides numerous times on black ice, ensuring we stop safely and continue on our journeys without trouble, save the folk driving far too fast on tyres that prove pretty useless in sub zero temperatures.