Matarić, M. J. (2007) The Robotics Primer, Chapter 2: Food for thought:

Q1: How important is it for robots to be inspired by biological systems? Does it matter what kind of robot you are building (biomimetic or not)? Does it matter if it is going to interact with people?

A1: I do think that not matter how small it was, all engineering has had some sort of inspiration from nature. Buildings were likely mimick caves, burrows and trees that provided shelter for early humans and other animals. Cars and train designs were likely inspired by horses and mules (i'm thinking horsepower of engines). Boats were probably inspired by leaves floating on water. Planes obviously mimick birds and helicopters were possibly inspired by some natural things such as "winged" seeds from maple trees or dandelion seeds. Even artificial intelligence is designed based off of a human brain and engineers are currently developing nano-bots for healthcare purposes which were likely inspired by white-blood cells. An argument can be made that almost anything that Engineers have designed has been based off of nature. But, without a doubt, engineering has the ability to use this knowledge to create different, sometimes better solutions.

It doesn't matter if you are trying to create a biomimetic robot, unless your goal is for your robot to as closely resemble something in nature as possible. I have seen videos of fish-like robots that can swim in water and snake-like robots that can slither and even climb. At this point in time it is fairly easy to distinguish that it is actually a robot, but there will come a day where some robots are actually sentient creatures that are indistinguishabe from natural creatures (on the outside). There are even humanoid robots that look so lifelike you would almost mistake them for a real human. This is very cool... and a bit disturbing at the same time. 

When designing a robot, if you are designing it to work with people, you have to make the robot aware of it's surroundings. The thing that matters most with robots, especially large ones, is that they can sense what is around them in order to keep people or other important things safe. An exception to this is manufacturing robots that are operated in evironments where there is no people usually or some other types like the Mars rover, where it needs to be autonomous but doesn't neccessarily have to be fully aware, since there's not likely creatures on that planet for it to harm inadvertently, but I guess there still exists a possibility. Even manufacturing robots, in an environment where no humans are required, would need other types of safety precautions likely such as visible signage providing a warning or making sure to shut the robots down if maintenance is needed, or some type of proximity sensors.