I have thought about doing the same thing because I shoot everything in one location. It would keep the backdrop perfectly straight if you hung it well. I would try it temporarily to make sure the color of the wall does not effect the shading of the cloth (color bleed through). If it does your software may have a more difficult time removing the green completely. The lighting could also cause a distortion if too much was to pass through the fabric. All that being said, I think every situation could be different. Just have to try it and see.