@flouncyfanny Apparently not uncommon! People fill a bag with it and it is essentially the same as the pre-made once. A step too far for me but I have come to appreciate that, on average, women seem to be able to hold it in longer and with less pain than men. As the child of a single mum, that was one of the big revelations of adulthood 
@GingerOClock Others will know more on this than me, I just bought more of shelf-stable stuff that my picky DH will actually eat. So my strategy isn't the healthiest (let's say lots of chorizo). I don't have an emergency bag beyond my normal stuff, because I do not think we will need it for Brexit. With that I mean, I have stuff I'd like to have in case of an overnight traffic jam in the car (blankets, water, food,...) but no prepared bag at home. Emergency bags are usual kept in case of a sudden disaster, when houses have to be evacuated quickly. The only thing I have done in relation to that is scan all our important documents and store them password protected in the cloud. People say to keep a paper copy in an emergency back but I know myself, I would inevitably trash it and have nothing left.
We are a healthy family, though, in a good weather bubble city, so the changes of us needing an emergency bag are pretty slim, especially on the go, as we have dogs we would have to pick up in the worst case scenario anyway.
Nothing wrong with getting a bit of a buffer in, just in case there will be any shortages after Brexit. I am currently out with the flu and have been really thankful to myself for getting all these tissues, meds, and soups. DayNurse me thinks it is great to not have to cough all over Asda. 10/10, would stockpile again.*
*need more hankerchiefs