You see it in alot of pages on the site. Honestly though I think it just looks bad and sloppy. I mean the purpose of this site is to tell visitors what a certain gun in a movie is. Not to just spit back an image or a crappy description that tells you nothing. I think all unknown weapons should be restricted to the discussion/talk page until they are identified. Otherwise it just looks amateurish.
A few examples of pages with "unknowns"
http://www.imfdb.org/index.php/Unknown#Unknown_shotgun
http://www.imfdb.org/index.php/Tango...rreled_shotgun
http://www.imfdb.org/index.php/Wire%...Barrel_Shotgun