Blizzard has been nerfing and removing those item weapons since WotLK, and if early reports are true, will probably do away with them completely in WoD. Blizzard is changing professions in WoD because of the incoming Garrison system.
Even if that doesn't happen, I don't carry any bombs or grenades on my toon. They literally serve no purpose. Frankly, the empty bag space is more useful.