Certainly are more light and compact than cans, jars, or aseptically sealed plastic (like the Dinty Moore stew trays). But costs more. Whether that form makes sense depends on whether one would expect to travel far from home on foot with lots of supplies, and how long one will want to keep them. November 2012? Conventional food packaging will do.
Imagine having to travel the interstate in a hostile situation. MREs allow you to eat without stopping. This could be very important under certain worst-case circumstances.