Orbs would be cheaper, yes, but they bounce off and are way heavier. They also are tougher to hit if the node is in an odd location like a cliff side. I use to do this prior arrows. Also, I don’t recommend the culling method. Finding meteors on EL is significantly tougher since they removed smoke and there’s no guarantee you’ll get enough in a radius. It may take a bit longer, but I can get way more star metal if I just use the old fashioned way.

Now the suggestion @erjoh made about using orbs in the creation of arrows could work. As I’ve said though, I’d prefer a 1:10, or even a 1:5 yield on them instead of 1:1.