I'm not where you are but if it's free, I don't really think it should be considered a "problem". All across this country stuff is being stolen to scrap out and it's really become a problem - I know as I was a "victim" of it.
We have a local fellow who hauls scrap to make money. My wife had his kids in school and I know his father-in-law very well. I had a bunch of scrap iron on the farm and I knew he was having a hard time making ends meet so I gave him a call. I gave him what scrap I had and how did he thank me? He came back when I was gone and stole all of my lead stash and electrical copper wire out of my shop.
No . . . I didn't "witness" him taking it but there is little doubt he did. I talked with the local PD about it (he is on their radar constantly) and they wanted to know if I wanted to swear out a complaint. I declined as I did not "see" him take it and but the time I discovered it, I'm sure he had already scrapped it out and blown the money. Funny thing though, my wife has run into him at the grocery store and as soon as he sees her, he turns and goes the other way. I keep hoping to run in to him so I can invite he out to steal some more lead and copper . . .
It may be a "inconvenience" but if it puts a stop to a lot of the stealing and theft, then maybe it's not a bad idea. At least it gives the LE a way to "trace" scrap if theft is suspected. Personally, I've stopped buying at the scrap yard and now just buy from someone who has "lead" (for BP) or "range lead" for sale at a reasonable price that has been smelted and cast in to ingots. A lot easier to have a 50 to 60 pound flat rate box delivered right to my door.