I'm reworking my recipe walkthroughs and have two things I think should be mentioned about frugality.
Yeast is a really big one. At the grocery store for $1.50-2, you can get yeast the way most people do. It's a little strip of three packets, 7 grams each, so 21 grams total. Next to it on the shelf are little glass jars for $4-5. Most people pass these over, since they don't see how they'll ever use that much yeast. It's 113 grams, though. Instead of getting 21 grams for $1.50-2, there are 28 grams in there. It's a smart thing to get, especially because it limits trips to the grocery store, but arguably frugal.
Enter the 2 pound brick.
908 grams of yeast for $3-4. I urge people to buy the little jar once for a small container you open and close and store the rest in a jar or bag in the freezer, airtight. I store all my yeast in the freezer, actually, and give it an extra minute in the warm water to activate. At $3 for the 908 grams, I get 302 grams per dollar. Even if you don't use the whole 2 pounds in the year or so yeast is good for (I'm still getting good results a year and a half after buying my 2 pounds) it's frugal if you would use at least 2-3 of the packet strips a year, which most people do in the holidays alone. Split it with your family, neighbors, or anyone else and you can not only get a year's worth of yeast for a few dollars, but also cut down on waste. The packaging used for the brick of yeast is negligible compared to that used for packets, and is easier to measure out of compared to the clingy packets that spill everywhere.
The bottom line? You can get 130 packets of yeast from one 2 pound block. That's about $62 saved per 2 pound block.
The other thing I found interesting was a problem I have with my green onions. While I grow them myself in the warmer months, the growth slows too much in winter to keep up with me. In order to supply myself with large, healthy ones I'd have to take up my whole deck with them from midsummer onwards, since I don't want to drive to my garden plot all the time for onions, and the rain and weather there would destroy them.
However, ones bought from the store tend to go bad in a few days in my fridge, even when put into water. The 50 cents for a bunch isn't the issue as much as the need to run to the store whenever my lust for them rises, which it does more often than not. I prefer to go to the grocery store once a week or less, and a special trip for green onions seems silly. I buy my 5-6 onions for 50 cents and use what I want that day, and stick them outside in a pot. They're large, beautiful onions like I'd get in summer without the months and months of waiting in winter, and fresh and lovely. My first group of onions outside was wilted and almost asking to be composted when I put them out. The life came back into them in a way that the jar of water couldn't provide, even in similar temperatures. I have my pots under floating row covers over winter, and the onions have regrown their tiny roots within a few days. I'm also experimenting with the roots cut off from using them, but no data just yet on that.
*update on onions* Onions I put in the ground in early December are still alive, despite a deep (12 degree Fahrenheit) freeze that even killed some of my peas. They lasted all winter!