Why the Obsession with Walking Robots?

Last spring, I worked on a project for a class measuring the risk of building an assembly plant in Southeast Asian countries for the Honda Robotics robot Asimo. In the process, I began to appreciate the robot that could walk, push carts, climb steps, and as it turns out, calculate its own path and determine if someone is going to walk in front of him so he can stop. It's amazing how much the little guy that measures somewhere in the 4 feet tall range can do.

But now this article in the Japan Times talks about how Japan plans to send a walking robot to the moon. Why a walking robot? The ones on wheels aren't good enough? The article says they are sending it to show how their technology can be applied, but I take that to mean they are showing it off to legitimize the time and money they have applied to developing it.

Why is there a need to have a robot with legs walking around in space. Humans had no control over their shape, but if they had, would they have chosen legs? Are legs the most efficient way to get around? There may be a study out there called "Legs are the Most Efficient Method of Moving," but I haven't read it. If it is so efficient and agile, why don't we replace the wheels on cars with legs? OK, I'm going overboard now, but you see my point. I respect the work they are doing with robots and think there might be some psychological reasoning for creating robots in our image; yet I don't think we need to send them to the moon because we can. For that, we should focus on the most efficient model for the task out hand whether it be sifting through moon dust or collecting rocks. Hey, isn't that Mars robot doing just fine?