I believe companies that include social responsibilities as part of their founding principles have a better position to work from in all areas of the business.  Mission statements, value propositions, product announcements all have a foundation on how the company presents itself to the rest of the world.  I'm not suggesting there isn't a profit motive in blowing your own horn about what a socially responsible company you are; but there is also genuine good that comes out of it, even if it is by accident!  Not every company can create a PR office, but internally being part of a tree planting effort, or an "adopt a street" campaign can certainly add some "team" benefits within the company. 

It can be hard to put a "Should" in front of a question (ask any parent!)  but I believe there is a social component to every entity.  It feels good to be part of something that gives back.