At the range I go to, they have a very nice 7 yard range that I do rapid fire drills on almost daily.
Official policy is that they 'discourage' rapid fire but the range guys don't seem to mind when I leave the ground littered with brass.
It's not even worth my time to pick up the brass when I can buy tumbled brass for $7 for a bag of 1000.
I shoot several hundred rounds a day, and I need to concentrate on the draw, the target, moving and firing, and I can't do that when I'm watching where I step.
Now for 357SIG, and .45 auto, yes, I stop and pick up the brass.