When it comes to food I crave variety. Admittedly my standard deviation on that scale is about 6! On the other hand there are certain flavors I won't eat. Olives! Yech! The common person doesn't cook. The common person isn't frugal. The common person won't grow vegetables much less meat.
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I feed my rabbits mostly wild forage. They definitely have their favorites. Ragweed is plentiful and they pounce on it. Goldenrod is OK. Wild Roses are candy. Thistle, prickers an all, are also a favorite. Mulberry saplings are appreciated as are maple seedlings. Staghorn sumac, the fresh branchlets, have made it on the table. It has been a dry summer, so the forage from my yard has been slight. But verges are prolific.
I have a rancher nearby who grows Sudex grass as greed fodder for his cattle, but also to break up the soil. He invited me to cut some for the rabbits and they loved it. I have a crop at 12" in my garden. It grows to about 60"! The 15lb bag of seed will last me years.
@Preitler 's point about wide variety of free or low cost food is well taken!
@eco2pia makes sound points too. Production requires separation. If kept together, well, they breed like rabbits! I think that is one of the main reasons they are not grown for production. Infrastructure is a big barrier for start ups. Meat poultry doesn't have much infrastructure. Egg farming balances infrastructure with production. Aside from veal, cattle farming is more about growing their food than any infrastructure, but ROI exceeds the machine and housing costs. Dairy is much the same, grow the food, SILOs of food, and some equipment. Add cheese and the equipment cost grows a bit, but the ROI is still great.