Why can't we all just go veg?

 Based on this blog post from big picture nutritionist Lawrence Haddad, "'Eat less meat' is seen as a way of improving the health of the planet and its people. However, eating less meat would harm the health of some individuals in low-income contexts, especially children under five and low-income populations...." The bottom line is that needs of consumers and producers both are different in richer countries than they are in poorer.