There is a marketing value in triggering subconscious ideas to give appeal to potential buyers.
The Stormtrooper helmet is a well known image that is held in our minds (unless you have managed to miss anything Starwars). Designers will learn from growing up with these images and they will be used sometimes to influence their design ideas and thus trigger responses in the public. Nostalgia adds to it too.
True originality in design is not that common. It will show up in something totally new and not seen before. Hard to find a good example though.
