I went food shopping today and I noticed empty shelf spaces throughout the store.

None of these empty spaces were large (by themselves) and they were of certain items of a certain flavor and brand.

This looked more like backorders that haven't come in as yet which may or may not be significant.

The amount of empty spaces is significant because it has not been that way before except as an aftermath of Katrina. After Katrina, The entire space allotted to staples such as flour and sugar were empty until the next truck would come in. This was not the case today, there would be other brands of the same product there.
The best luck is what you make yourself!