I appreciate your thoughts here, Katie. It's a good point—cheap food tends to be less nutritious, so it can be hard to spend more for better food. I'm sure others have done a sophisticated analysis of this, but we don't factor into our food choices the greater healthcare costs of a poor diet. But of course the effects of low quality food tend to be very delayed, so there's little incentive in the short-term to pay more. Most of us (myself included) probably wait till we have a problem before making different choices.

One at least partial solution is to make more of one's own food. High quality homemade bread, for example, is way cheaper than probably even the low-quality store bought stuff. It takes time, obviously, but makes for more healthful and budget-friendly results, and also keeps us more connected to our food choices. Thanks for your comments!