We're not even talking about "garbage". That's different.
Garbage is big biz too, but it's a whole nuther industry altogether. We're talking about junk here.
Does your car have aluminum wheels? Pretty much all of them do now. If you run your car into the curb and crack the wheel, that wheel is worthless, right? Well, no. It isn't. It's worth .65/lb at the local scrap dealer here. Figure $10 or $12 for that busted wheel.
That's not a bad price for something an idiot would throw in the garbage.
A dead barbecue grill is another $10. (Just the aluminum tops, not the legs and stuff) I know a guy that goes around after Father's Day and scoops them up off the curb. Father's Day being your big day for buying barbecue grills. He pops the tops off with a crowbar and nests them together so he can get more in his pickup. It takes him about 10 seconds to harvest each one.
Last Father's Day he grabbed 35 of them. In the middle of a depression. Not a bad day for picking up "junk".
Now multiply that by a few million tons a year. That's the "junk" business. Not to mention the rebuildable cores for starters, alternators and stuff like that. That's not "junk". But it is money.
Cash flow? You bet your ass.