I imagine that most shooters here already do so, but if you don't collect your brass please do. I'm always amazed at just how much spent brass is lying around my local range with not a soul in sight. Even if you're not interested in reloading the scrap value is worth the little bit of time it'll take to pick up your shells. When this 5 gallon bucket is finally full I hope to either be reloading at that point or scrap it and re-invest the cash into ammo. I'm over 3/4 full and last time I checked it was a touch over 40lbs.
Here's a good example of brass left by someone at my range; all the 9mm casings (only 6 - 8 .308 shells of mine in there) were on the pistol range in a 10' area:
CowTown Feed & Livestock ("Your local used cow dealer") is where I buy dog food ... I nearly brought home a stray they've taken in. The shop owner thinks she's @ 9 - 10 months old and is so friendly it was hard to leave. I may be returning on Monday!
Kind regards, B.