Blizzard, Why So Lazy?

The practice of recycling old item models (the "new" Masterwork Elementium Deathblade for example) and icons (Feather Lure == Slow Fall) stands out to me as blatant laziness on the part of Blizzard Developers.

Yes these are only 2 examples but as most people are aware it is a growing issue.

So I'm asking.. What's the deal Bliz? This doesn't strike me as some huge cost prohibitive issue, so why keep on reusing previously developed objects when new ones would add clarity and originality to game play?