Re:How Many of You Do Portioning and Pre-preparation?
I don't obsess about it like some folks do, but since there are only two of us I quite regularly buy things in the larger packaging (meat, especially) and then split it out into portions that make a meal for us. I certainly don't keep separate freezers, nor do I make a point of having enough food to feed us for a month in the event of the apocalypse, but I do have quite a store of food on hand most of the time.
Saving bacon drippings doesn't fall into this category for me, as I do it because I love how things taste when fried in it. Has nothing to do with saving money. Most things like sauces and stocks I do several gallons at a time not through some effort to save money but because I don't know how to make less than that much, so I always have some in the freezer. Whether or not I save vegetable parts that would normally get thrown out depends on how much room I have in my freezer, but I pretty much always have a ham bone or two, at least a couple of chickens' worth of bones, and various containers of pan drippings if I didn't make gravy when roasting something.
The only time I buy things ahead specifically to freeze because they're cheap is in summer, when local produce is practically being given away. I chop onions and peppers to freeze, and my niece and I just started doing our own broccoli and cauliflower last summer. I also freeze or dry herbs from my garden, but that's not so much about saving money as the fact that they simply have more flavour, and what I preserve will last until more grows.
More than shopping ahead, I shop on sale. Rarely do I buy anything outside of the staples that isn't on sale that week, although I will make an exception if I have a specific recipe in mind or a party to attend. Most often, I end up basing my meals for the week based on what is on sale coupled with what I have in my house.
And then there are the days it comes in handy, like today. I found out on Friday I had to make Easter dinner, but I was working solidly all weekend and couldn't get to the store. I had bought a ham purely because they were on sale, and the rest of the dinner came from my freezer and pantry.