From reading the grandparent:

"subsistence farmers are net consumers of their staple crop. In order to survive, the poor diversify across a variety of agricultural products"

I don't understand the downvotes for the parent. They are growing other products, or have cash from other activities, and use this to buy the staple they can't grow. If price of staple rises and price of other products and services does not, they can't afford to do this. The beneficiaries are large industrial farmers of the staple. Did I miss something?