my bags for my vehicles were like this,then i compressed the mre's down out of the original packages.
it gained me a bit more room.

Strip out all the junk in the MRE's you don't need or want. The accessory pack is the first thing I get rid of. I've got a lighter, don't need the matches. They suck anyways. The gum is garbage. The beef jerky is compressed dog vomit.

Take the side dishes out of the cardboard. If you're actually going to use your MRE heater, keep only the entree cardboard. If not, junk that too. The toilet paper is only good for starting fires. I'm sure you get the idea.

Then put everything you're keeping back in the MRE bag, squeeze the air out, roll it up and tape it shut.

open the mres, trash the small parts, keep the flat packs of food out of the cardboard (entree/sides/desert) either put them back in a MRE outer patch and reseal, or just wrap up in some tinfoil





http://www.lastalive.com/survival_guide/long_term_survival/food/mre-saving-space.html