A range/gun shop that I drive past for work picks up all brass left around and sells it on their shelves "sorted" by caliber. They are in 10lb boxes and are $10/ea. I get all of my brass from them and dont get upset when I dont get them all back from my range.
If that's true, you need to buy everything they have, every time you see it.
$1 / lb is less than half of scrap
value, let alone resale value.
(*Cartridge brass has been fairly stable, at $2.40 to $2.80 per lb, for the last 1.5-2 years. There is the occasional spike to $3+, but it hasn't really gone down.)