A vegetarian diet is i) requires less land and energy, ii) as a result is cheaper and iii) per $ is as nutritious as factory farmed meat. People in poverty eat very little meat. In fact, all meat production and consumption, in addition to factory farming, can be objected to on the further ground that it raises food prices for the poor: http://www.nytimes.com/2008/01/27/business/worldbusiness/27i.... This is inevitable as meat production is 3-10x less energy and land efficient as eating plant products.
Finally, do you think that the chickens do not die?