Man, the USA sure is a widely differing place.
We have had laws here regarding selling scrap for ten or fifteen years at least that are WAAY tighter than what most of you describe- they have been around for so long that we all consider them completely normal.
I have had scrapyards call me up and ask me if something was mine- it was, it was stolen from a pallet in front of the waterjet cutter's shop- because they routinely hold suspicious stuff, and call the police, too.
Read the current law here- it would eliminate most of the shenanigans that you seem to live with-
"SB5312 and RCW19.60 will require the following for recordsby recyclers:
• Date, time, value, location, and signature of seller.
• Name of employee purchasing the material.
• Name, Address, Phone Number, of customer selling material.
• License Plate, and State of which it was issued, and descriptionof vehicle.
• Current Valid Driver's License or other Government Issued I.D.card number, -or- a photocopy of thatcurrent driver's license or equivalent.
• A description of the material sold, plus YOU MUST INCLUDETHE ISRI's code word, or equivalent along with your descriptionof the material. Example.: Yellow Brass - HONEY RadiatorsOCEANe t c. .
What you can & cannot buy, and from who:
• Recyclers can not buy any non-ferrous metal property fromanyone without a current government I.D.
• Recyclers can not buy any commercial metal property' fromanyone who does not have a commercial account with the recycler,prove ownership with written documentation, or showdocumentation that the seller is a employee of a business authorizedto sell this kind of material.
• Recyclers can no longer buy burnt copper wire, unless you providewritten documentation of a 'legal burn'.
• Recyclers can no longer buy kegs from anyone, except a breweryor keg manufacture.
• Recyclers cannot buy materials from the same customer morethan once per day.
You cannot buy scrap metal from anyone with the followingconvictions on their criminal record within the past 10 years:
• Any crimes involving drugs.
• Any crimes involving burglary.
• Any crimes involving robbery.
• Any crimes involving theft.
• Any "Possession of" or "Receiving of" Stolen Property.
• Any "manufacturing, delivering, or possessing with intent todeliver methamphetamine, or possession of ephedrine or any ofit's salts or isomers, or salts of isomers, pseudo ephedrine, orany of it's salts, or isomers, or salts of isomers, or anhydrousammonia with intent to manufacture methamphetamine"
• Whether the person is acting in his or her behalf, or as the agentof another"
and here, if its over 30 bucks, they are required to MAIL you a check. No cash. No cash, ever, its always a check, under 30 bucks you can get one right now, over, its in the mail.
I do get a pass on some of this because my recycler is also my new steel supplier, and I have an account, so, with ID, they will actually give me a check for over 30$ at the time, because they have all my info, including bank financials, on file. But walk ins, forget it- they check id, and they mail checks.
This cuts down on a lot, although of course not all, of malicious scrap stealing.