Years ago there was a train derailment carrying a whole bunch of GM vehicles, mostly trucks and vans, near here. I knew the guy that bid for and won the salvage contract with the insurance company. A representative from both GM and the insurer stood and checked off each and every VIN as the vehicles were one by one fed into the crusher 100% complete save for fluids, batteries, and tires. And in many cases, only superficial damage had occurred, and the vast majority of the vehicle, even if you were not wanting to fix it, had most of its unboltable parts in perfect order.
And for those of you that think the crusher, and then the shredder, cannot handle the whole car? Think again. They obliterate EVERYTHING down to chunks no bigger than your fist. Cast iron engine blocks, crankshafts, differentials, all of it. Every last bit. Comes out the other end on a conveyor belt and you'd be hard pressed to identify any piece at all. Just a bunch of hot gray chunks. The lighter stuff, called "fluff", is blown up and out on to a different belt. It is an awe inspiring sight to see. I watched a 1978 Mercury Grand Marquis, which was already flattened, be fed into the shredder and inside of about 45 seconds it was GONE.
Big hub here for salvage, down by the Mississippi river, where the stuff gets loaded on to barges and shipped down river, then loaded into giant ships and sent to usually China to be made into all the cheap crap you see at Harbor Freight.
Scrap value is WAY down right now, though. So there are lots of stockpiles all over the place. The metal salvage industry "starves" the places that need it for a while until the price starts to go up. Then it is a game of hot potato. You want to hold on to it as long as you can so you can sell high. And it makes a difference. At low points, a semi load of flattened cars is barely worth the fuel and insurance and operator costs to bring it from say 100 miles away down to the riverfront. But at boom times, it can be worth 10 times as much, and you'll see salvage companies like Grossman running 24-7 trucks up I-44 for a solid month.
I used to do a lot of scrap business, but it just does not pay like it once did. Now it is difficult to get rid of it unless you have a LOT at one time to make the collector worth his trip.
It is on a pretty strong upward swing right now, though. Not at the highs it once was, but at least it is going back up. Certain metals, like copper and brass, never really dropped like unclean steel (cars) did.