You can get pound of TVP or soy protein is like $3-4; and certainly less at wholesale prices. It comes dehydrated, so back of the napkin I'd guess the cost for a company producing fake meat products is like $1/lb or less.
I paid $8.50 at a gas station for 2.47 oz of "Noble Jerky." Ingredients: soy protein, sugar, black bean paste, spices.
I imagine the profit margins for these products approaches that of soft drinks.