Some of these people are prepared. But there is a difference between someone who is prepared and someone who is just living to be prepared for the end of the world.
On the commercials for the show I saw this obese lady saying "I'll have enough food" or whatever. Yeah, you'll end up starving later though.
Depending on the nature of the crisis, maybe, maybe not....
If it's a Katrina level crisis... where it's just the zone you're in and you need to hold out for help, a few weeks or couple months of food and water should see you through to rescue even under the worst rescue situations (which given FEMA's track record, you might want to expect)
However if it's a much larger economical meltdown and food distribution simply falls flat on it's face... you'll need to find land on which you can grow your own food, and you'll need enough food to last until harvest. This situation is far less likely (though honestly still a potential reality) and you'd need a lot more food, and seeds, and a destination (or multiple should the first prove invalid due to circumstances at the time) as well as a way to get there (fuel could be a rare or even unavailable resource)
In this situation there is no rescue... and quite frankly survival would be slim even if prepared... of course, this is also a much more unlikely scenario.
The former scenario on the other hand does happen... we haven't mastered total control over nature and major earthquakes/tsunamis could wreck extensive destruction.
It's not paranoia to recognize these potential events.... it's common sense.
Paranoia is dwelling on them and living your life in perpetual fear of them. Having reasonable preparations is just... well... reasonable, even if potentially (and hopefully) unneeded.
Last thing you want is Murphy's law biting you in the backside during a crisis