No, really, they're probably worse that the rest of us capitalistas.
http://pss.sagepub.com/content/early/2010/03/01/0956797610363538.full
Now if they would only do this experiment on some God-fearing types, it might be even more interesting...
...Experiment 1 confirmed that people attach higher social and moral values to green than to conventional consumerism. This finding leads to two markedly different predictions: On the basis of research on behavioral priming, we predicted that mere exposure to green products would increase subsequent altruistic conduct; however, on the basis of recent theories on moral regulation, we predicted that purchasing green products would reduce subsequent altruism because it establishes moral credentials. Experiment 2 tested these predictions using a one-shot anonymous dictator game...
http://pss.sagepub.com/content/early/2010/03/01/0956797610363538.full
Now if they would only do this experiment on some God-fearing types, it might be even more interesting...