Of course, these methods do have their drawbacks. The first is that it is time- and labor-intensive as you can see from watching the videos. Another downside is that food packed in such ways is typically not going to be something you can just jump in and start eating. Raw wheat, for instance, must be ground into flour using a countertop mill and then baked into bread. A 5 gallon bucket full of wheat will make a lot of bread to feed you and your family, but that level of work going into preparing it may not be what you're looking for in an emergency. If your personal preparations tend toward gearing up for a long stretch of bad times, then this method is by-far the best for you due to the many months of food you can quickly and economically accumulate. If, on the other hand, your preps tend toward shorter emergencies (i.e. blizzards and/or ice storms, floods, or even self-quarantine during a bird flu pandemic) you might find it better to simply load up your pantry with canned goods. With few exceptions, virtually any commercially-canned product you buy in the grocery store will last at least 2 years as long as it is not exposed to high temperatures for extended periods and there are no noticeable abnormalities in the packaging (i.e. bulging cans, etc.). In fact, many are still good long past the expiration dates printed on them. Those using this method must be diligent about rotating the stock in the pantry on a regular basis, meaning you must get used to using the oldest items first.
A sort of middle-of-the-road option and the one that I use mostly is to buy commercially-canned dehydrated and freeze-dried foods in #10 cans. The downside to this method is, first off, it's more expensive. Secondly, you'll often find these products are not available locally, and so you must pay for shipping as well. Still, when you factor in the *LONG* shelf lives of these foodstuffs, I believe the added cost is worth it.
For those who may not be familiar with food storage as an emergency prep, dehydrated foods are usually base ingredients such as rice or beans with little or no seasoning added. You typically add them to boiling water, which rehydrates and cooks them at the same time. This can be done on the stove, in a crockpot, or even over a camp fire. Things like pancake and muffin mixes are also typically dehydrated. A personal favorite of mine are dehydrated Potato Flakes, which make mashed potatoes when you fix them. Mmmmm... mashed potatoes.
Freeze dried foods, on the other hand, are typically already a meal that just requires rehydrating. Just pour some odd-looking powdery concoction into a pot of hot water and let it sit for 20 minutes or so and return to find that it has magically soacked-up all the water and turned into a steaming pot of yummy Chili Macaroni or Chicken Teriyaki, all pre-cooked and seasoned and ready to eat. Most freeze dried foods are typically advertised as having an almost unbelievable 25 year shelf-life if left unopened.
As always, it is up to you to decide which is your best option for putting up a larder of storage food. Only you can decide what best suits your individual situation. For me and mine, I have concentrated mostly on dehydrated and freeze-dried so far, but I am planning to put away some bulk beans, rice, rolled oats, and pancake mix in 5 gallon buckets with mylar liners and oxygen absorbers in the next few months.