One of the things I see is the energy impact to make concrete as Industry scrambles to find a 'greener' concrete
It takes a lot of energy to make it, and the world is using billions of tons of it. Makers are finding better ways to do it.
http://www.csmonitor.com/Innovation/Tech/2008/0312/p14s01-stgn.html If impact on the environment in total is a concern then earth bag would win hands down.
Saying that even using Concrete if used long enough compared to say wood the total environmental impact
goes down over time.
It probably just comes down to personal choice and funds available as I would be happy to use either system.
We drive our cars on it, we build skyscrapers with it.
But concrete, one of the most common building materials in the world, has an ugly secret: It's a major source of carbon dioxide (CO2) emissions, which contribute to global warming.
Roughly 5 to 10 percent of global CO2 emissions are related to the manufacture and transportation of cement, a major ingredient of concrete.