Well, I have the ‘prepper’ mentality. Most of us are concerned with - and prepare - as to how we’d survive in dire circumstances; especially if we live in urban and suburban environments. Protein combination is part of that. (Brown rice doesn’t last long and remain healthy in long-term storage; neither does whole grain flour, unless you store it as berries.) And I never said that we don’t need other types of food than what’s available from grasses and grains.
Anyway, Good Luck with remaining ‘pure’ if everything around you goes to hell.
As long as I live in a rural area where we grow food, have apple orchards etc, my prepping can include have healthy food. I do have whole grain flour and brown rice as prep supplies, but there is a retail organic mill not too far away. And we all have our own gardens and/or chickens, etc, as well as many working ranches around, so the prep is a little different. I tend to be a bit of an end-timer, but I’ve lived in the country most of my life, so never prepped in a city...