I honestly cannot see exactly how one could proclaim this sort of case as "green." If this was marketed as an artistic case, I could've accepted that. But as trying to be environmentally-friendly, this is likely anything but.
While it might not burn at a temperature that plastics melt, I'm pretty sure it'll still wear out far quicker, and be far more susceptible to water damage, such as even just damp air. Plus, it'd be impossible to keep clean; invariably, I can see this case being more likely to be thrown away rather than recycled compared to a metal case, which is equally as recyclable, if not more given that metal tends to cost more to produce new than paper products, yet both cost much closer to each other to recycle.
Basically, I see this just as a novelty case made to fleece some naive people of their money and nothing more.