Really, the big win is going to be "efficient air conditioning for poor countries" and "using materials other than concrete to build." Everyone loves AC. The more money you have the more you use it. And everyone in poor countries uses concrete to build. The bad thing is that these two things combine: the concrete box that is your building heats up like a brick oven, making AC work more. Doh!
You can add a bit of insulation inside the concrete to make the house require less cooling than (any?) wooden house.
(I really thought it would be about concrete CO2 emissions at first.)