Avian flu is but one of many structural break downs.
Fact is that you get serious break downs in society every so often, and Britain has merely been lucky.
Tinned food is OK, but heavy, what if you have to move ? Also what about water ?
People very rarely die directly from hunger, but instead from malnutrition induced disease. Thus food supplements are lighter and are more easily hidden if you think things are going to get very bad. Freeze dried meat lasts a very long time.
1918 was a quite different event to anything we can expect now. The system was appallingly inefficient, but anything that left people alive would leave it intact.
Now the majority of food requires 2 or 3 levels of infrastructure for distribution. Power, fuel (& power for fuel stations), apckers and truckers. Fortunately very little food is carried by rail which is pathetically vulnerable.
The government's plans are frankly scary in their ineptitude, being basically spin to "prevent panic". The priority for vaccines is what you'd expect of the political classes. They are first, then the media, and then the NHS.
What about transport workers ?
Power stations ?
But even if they got all the "right" people what about their families ? Would you go to work if you might bring back infection that would kill your family ?
Do you trust the government to tell you the truth about the risk of this ? Really ?
This is quite independant of party, recall the Tory lies over BSE ? Labour with foot & Mouth ?
The BBC will do what it's told, not least because they are the people who brought us the MMR scandal.
We very nearly had a famine during WWI when they brought in harsh anti-hoarding measures, and caused veryone to use up and dispose of their food stocks in a little bit of a panic.