Two sides to this that I see. I think showing limited quantities of stock is a deliberate marketing ploy, to be honest, no differently than an infomercial telling you to ACT NOW BECAUSE SUPPLIES ARE LIMITED!! If they showed an enormous supply (relative to average sensibilities), people would tend to relax and take their time. If they show what looks like a shortage, people get anxious and are willing to buy more in a shorter time.
The other side to this is that supplies really are limited - just not on scales and timelines that most people can comprehend or relate to. If people knew what was really happening, there really would be a rush, as all supplies are exhausted. However, the alarmists have the opposite effect, as people become desensitized and go to sleep. The Titanic might have just hit an iceberg, with two hours before it sinks, but it's floating now just fine, so what's the problem? There is time. Or the weather inside the eye of the hurricane is so calm that it is inconceivable to the mind that things are going to get very scary, and very soon.
In a strange way, we have the alarmists to calm our fears, because they look so ridiculous, so out of place in contrast to what looks like business as usual going on around them. Some hear or read a Porter Stansberry report for the first time and want to run screaming down the street. They make an immediate purchase, as they buy up food stuffs and baton down the hatches. Then tomorrow comes. Prices have gone up some, but otherwise the ship is still afloat, despite the water it has taken on. Then a barrage of what looks like cheesy multi-level marketing garbage floods into the inbox, all filled with "Secret Inside Information" from the doomsayer. And the feeling of "Oh crap, was I taken in by these people?" hits. Well, yes. And no. Yes, you were taken in by them, and are a mark, and no, they aren't wrong. In the long run, what they are predicting is inevitable. But that does not mean that life does not go on. Today, tomorrow, and even when it hits. Just be prepared. You don't know how much time you have to prepare, but panic is not going to help. Just take the necessary steps for today and let providence rule the details.