One more thing, then I'll be done posting on this particular thread.
If you're packing a bag that you plan of living out of for an extended period of time, I'd encourage you to try to use it some time as practice.
I know the first bag I packed for "bushwacking" in the back country wound up having some pretty major flaws (no bug net, non-waterproof sleeping-bag, no TP, too many clothes). I imagine many of you will find the same thing. Giving your survival kit a trial run before there's a real emergency will give you a chance to add any forgotten necessities, and dump any excess weight.
And, when you're actually trying to cover ground while hiking (the only reason I can think of to be on foot in an emergency would be to make it somewhere safe quickly) you're going to feel every extra ounce. If you ever have a chance to hike the Appalachian Trail, you could almost entirely equip and feed yourself with stuff that's been discarded at the shelters by other hikers in an effort to cut weight.
If you're planning on being in a car weight is less of a concern, but you still may very well find there's stuff you forgot, and stuff you don't need. Or you may find that - after eating subsisting on them for a few days - you wind up still liking some bits of you food supply, hating other bits.
If you're staying at home it's super easy. Buy an extra couple of cans of food or bags of dried beans every time you go shopping, and pretty soon you'll have weeks (if not months) of non perishable food on hand. Add a wood stove, a couple of solar panels on the roof, and a hand-pump on your well, and you may not even notice that there was an emergency.