I had a meeting with the Director of SLC Greenbike last week regarding this. It's a huge and growing problem for many cities in the US. Apparently the business model for these operations is modeled after Uber or other tech startups--don't worry about profits, just get investment money and dominate the market/run other bike share companies out of business by offering the service free of charge to cities.
The bikes average $200 each and because of that they are being used as a disposable resource. They're being discarded, damaged, and vandalized at staggering rates in places like Dallas.
And Seattle is now starting to see similar problems.
I don't see it as a sustainable solution to transportation: if we're going to start seeing entire landfills full of bikes (i.e. the photos from China), that seems to undercut the argument that bikes are a more sustainable solution than other transportation options. And the bigger danger is that the companies offering this new model (Limebike, for example) have no long term model. They've been operating at a loss since inception and will continue to for the foreseeable future. If they replace more sustainable models, then pull the plug because they lose their investment funding, it will set the whole bike share movement back years.
As for just using the discarded bikes in your local co-op, I'm also skeptical. If they're not being used by the bike share company, the assumption is they're damaged. I can't say for certain whether it would be cost effective to repair and repurpose a fleet of bikes that were barely usable in the first place because I haven't had first hand experience with them, but I'm skeptical.
Just my two cents