I think it's because it evokes the look of black and white film, whether movie or still photography. In fact I just picked up 'The Last Steam Railroad in America' by O Winston Link and Thomas Garver.Excellently composed and executed photographs of steam locomotives, made by a semi-professional photographer with an extensive background in civil engineering. Well worth a look, and copies of the book are currently inexpensive.

Some photographer (Ansel Adams IIRC) observed that color was good for just making a picture, but with B&W you can establish a mood.