Delta_G:
The problem is that you can't ever be sure what's going to happen. Remember when the CDC put out the guidelines for aZombie Apocalypse and everyone laughed. And they came back and said if you're ready for that then you're probably close to ready for anything that might really happen in real life.Now if you mean being ready to be self sufficient and not being reliant on the grocery store to feed yourself I'm all about that. GROW YOUR OWN! Not only does it protect you if something bad happens it also gets you far superior food taste and nutrition.
And really, it isn't all just about doomsday scenarios. There are all kinds of natural disaster scenarios where modern conveniences break down for a few days. It's smart to be ready for something like that.
I agree to an extent. The problem with the preppers is that they see a hazard (which is real) but do not asign a risk to that event actually ocurring ( often vanishingly small ) and they then literally devote their lives to boxing shadows.
In general I would not expect preppers to be that much better off than the general population if an unexpected event occurs.
Also don't underrate human resiliance. Look at the tsunami in Japan. Just a few weeks after very much of the country was restored to normality.
You are correct that there are lots of hazards out there. You are also correct that people in general should be more self sufficient. More important though is that Governments should protect their citizens against real hazards that have a high risk of happening e.g. fatal flu pandemic - but they don't do it.