Furthermore, going after scrap metal sites makes an important business harder and fails to be inquisitive enough about the reasons why the thefts happen at all. Maybe we should try to understand why people are stealing copper. (Presumably poverty, drug addiction, lack of opportunity)
If you believe we can just fix poverty and drug addiction with some government program, I have a bridge to sell you. So far, no one has, anywhere in the world.
Many people (and once they get themselves addicted to something bad, that rises to "most") are just terrible and care only about their own short-term gain. They'd do any amount of destruction to others for some small temporary profit or fix.