The majority of corporations environmental groups are part of a marketing organization. This group can be used to coordinate the grass roots efforts in the company as employees are passionate about making a difference in the world beyond just shipping their services.
Here is an example at eBay Green. https://twitter.com/eBayGreen
But, sometimes the green efforts are primarily wired for damage control. An example is here in this Economist article on China's hydroelectric dams.
Yet it does not matter how strong the case may be against Xiaonanhai, because the battle against a hydropower scheme in China is usually lost before it is fought. The political economy of dam-building is rigged. Though the Chinese authorities have made much progress in evaluating the social and environmental impact of dams, the emphasis is still on building them, even when mitigating the damage would be hard. Critics have called it the “hydro-industrial complex”: China has armies of water engineers (including Hu Jintao, the former president) and at least 300 gigawatts of untapped hydroelectric potential. China’s total generating capacity in 2012 was 1,145GW, of which 758GW came from coal-burning plants.
There is also a political reason why large hydro schemes continue to go ahead. Dambuilders and local governments have almost unlimited power to plan and approve projects, whereas environmental officials have almost no power to stop them.
Here is where damage control is used.
Environmental officials who have not been financially captured by the dambuilding economy find themselves as scarce as some of the fish they are charged to protect. Environmental activists, meanwhile, can request access to public records and demand public hearings, both required by law. But they say that these avenues are barred when they are most needed—on controversial projects that face vocal opposition. For example, the authorities have rejected requests for public records on Xiaonanhai and they have not granted a public hearing.
This is something I learned over 5 years ago when watching how one corporation had its environmental group set up, and I knew it was not really that interesting to me as they were like a faux green effort.