They could make a rule that you have to paint your backside blue too, and there would be Torys who complied because it was the right colour.What has happened in some parts of Wales is that people are coming and going to shops - and buying up stock that is in short supply.
The rules have not been well written and explained - and some might not be justified in terms of science or evidence. But stay at home except <list of exceptions> is pretty clear and, I suggest, does not include driving for an hour even if there were no intention of getting out of the vehicle.
By the way, are open-top cars acceptable?
I prefer rules that are logical and not just for the sake of exercising power over people.