As a follow up to the comments on that last post, here are some links to research on the subject of pricing and social responsibility.
Consumer Pricing Premiums for Social Responsibility, Laroche, Bergeron. The following is an excerpt from the executive summary at the back:
In 1989, 67 percent of consumers stated they were willing to pay 5 to 10 percent more for econolgically compatible products. More recent surveys have suggested that significant numbers of consumers would be willing to pay up to 40 percent more for a "green" product.
The research shows that consumers willing to pay more for environmentally friendly products are more likely to be female, married, with at least one child living at home. This group seems more likely to put the welfare of others before their own.
And from an investor responsibility perspective, this one keeps coming up:
The Eco-Efficiency Premium Puzzle, Derwall, Guenster
On a related note, Google scholar provides great results, but nothing is cached and everything is part of some journal that requires logins. Use the "web results" link below the search result and you almost always find a publicly accessible version.