I can imagine what you mean with building up using different materials, thinking about the past and knowing how vulnerable wood is without treatment and how easy it could be destroyed with moist soil, water etc. it is understandable that those people tried to think out something and maybe that was it a combination of stone and wood, actually it looks really nice this way because of originality. I like those shutter on windows, they still let the light to penetrate but even though it might be still enough protection from light in hot days :)