The main reason I've done this is that I want to try giving the enemy shields a hexagon pattern (like player shields). Currently, the hexagon effect on enemy shields is created by letting that background show through.
Enemy shields all use the same image, so it won't scale properly. I still want to see what it looks like, though.
The odd thing is that, if you look at the actual background image, it's weirdly smudged. It's not a clean hexagonal grid. Not that it matters much, as you don't notice it in the game.