[Fleecewife]

I really don't think the advice was meant for some cataclysmic disaster scenario.  Over the pond they seem to think their own government is their enemy, hence the firearms and weaponry.  What Police Scotland were suggesting is that people should be prepared for life's small emergencies like getting stuck in a traffic jam for 5 hours with a screaming baby and kiddies needing the loo and something to eat, or being caught in sudden heavy snow and needing to keep warm until rescue arrives.  I think to be prepared for that makes massive sense.
As you say, for something more earth shattering, we have our land, our stores, our cosy houses out in the wilds and many of us are used to surviving on what we produce ourselves, so staying home is best.