Why do people buy green products? A new study (h/t: Charlotta Mellander) finds that green purchases are less about energy savings or cost savings and more about image. Prius owners pay a significant premium over many conventional fuel-efficient cars. When asked about the top motivating factors behind their purchase, the comment, "makes a statement about me" was at the top of the list, while "higher fuel economy" came in third, and "lower emissions," fifth. The authors argue that status plays a big role in green purchases.

Because biologists have observed that altruism might function as a "costly signal" associated with status, we examined in three experiments how status motives influenced desire for green products. Activating status motives led people to choose green products over more luxurious non-green products. Supporting the notion that altruism signals one's willingness and ability to incur costs for others' benefit, status motives increased desire for green products when shopping in public (but not private), and when green products cost more (but not less) than nongreen products.