No, I'm not talking about magical pollution.
Specifically, I mean how with Fabricate you
Choose raw materials that you can see within range. (120 ft)
Nothing about needing materials to occupy the same spot as the finished product.
This strongly implies that you are moving actual materials in the world to form a 10-foot cube at a location you desire. Could you use this to move a rock out of the way? To dig a hole? Clear a forest?
The amusing implications are whether you could form a (small 5-ft cube) cave in a rock wall while making a nice statue made of the rock, or a really lazy wizard clearing all trees in the nearby area to make a giant pile of firewood.