Freeze driers are quite costly to buy, but one of the benefits I've found is prepping against inflation costs. Buying up cheap food now and storing it against future cost rises has already been worth it, for me. I've seen things go up from e.g. £5/kg to £7/kg in just the last few months. Also, if my freezers go down, the freeze dried stuff is fine. There's no ongoing cost to run a freezer full of food that's subject to mechanical failure and blackouts.
There is a definite up front cost, and there's no guarantee that the freeze drier will carry on working any more than the freezer will. Overall, if rather have some cheap food on the shelf that I can cook with boiling water, than a freezer full of stuff I can't cook if TSHTF because eive run out of gas. There's no way I can afford to freeze dry everything, nor would I want to. Being able to go to the wholesalers and buy up four turkey crowns for less than £25 each and keep them for years, has been useful, though. How much will a cooked turkey crown cost in a year's time? Or even five years?
Some of the prices are a complete rip off - 40g of freeze dried peas on Amazon for £.7.98. Equivalent to £199.50 a kilo! And that's reduced!
https://www.amazon.co.uk/Supergarden-Fr ... 07GLTSK1M/
If I could go into business selling freeze dried food, I reckon I would. There's got to be a profit margin in that.