I once got nearly banned for explaining to newbies that if they were just starting out, having to buy all their jars and canning supplies, didn't grow/raise/hunt their own food to put in the jars and would have to buy it, plus the cost of the energy to preserve it, at that time my calculations indicated that if they were cash strapped, they would have been better off buying commercially canned food at sale or bulk prices.
You would have thought I cast aspersions on some people's grandmas, they way they reacted. I was thoroughly pummeled, electronically of course. Kill the messenger was the order of the day!
Yes, of course I realized that home preserved foods are usually more flavorful and have more vitamins retained. Yes, I realized that we can home preserve wonderful, heirloom varieties that are never available commercially. Yes, I realized home canning smacks of independence, self sufficiency and the American way (cue patriotic music). For Pete's sake, I spend half my summer slaving over a hot canner. But I do it for the quality of what's in the jars, I already have my equipment, and I have my own fruit, vegetables and meat to can. So all I have to buy are the sugar/salt, lids, water, and power. For some young family, really struggling to make ends meet, with nothing already in place other than hungry mouths, it is really hard to be able to beat the cost savings of judiciously purchased commercially preserved food. (Or at least it was back then, about 5 or 6 years ago.)
But the bottom line is that I was concerned about some new folks who seemed to be very short of money and were stressing about getting all the stuff everyone of the old hands was telling them they needed, when I doubted whether they could even afford the food to can after they bought all the rest. People just didn't want to believe that sometimes, the preferred method is not necessarily the most cost effective.
By the way, is it just my Doubting Thomas side showing, or is it not surprising that a website that promoted dehydrating found that dehydrating and other forms of home food prep were most economical? Another by the way, I never went back to that subforum ever again. The moderator was one of the gang who jumped on me because they didn't want to hear my findings. I learned that home canning is a sacred cow in certain circles, but I made the mistake of thinking that the truth would win out. Silly me.