There was an old Seinfeld episode where Kramer drove a truck full of aluminum cans through several states to get more money. Great episode if you haven't seen it. He's running out of gas and trying to catch a thief. The only solution for him to have any chance with the thief is by throwing trash bags full of aluminum out onto the highway to reduce the weight of the truck. And then he pushes his chubby friend Newman out the door to reduce the load even more. A funny episode.

I believe (fairly sure, but not positive) that if you drove a load of aluminum cans across state lines that would be illegal. People pay deposits on the cans when they buy them and I think the intent of the law is to get the money back to the original purchaser, not someone else. Also, if you bring in the cans from out of state, there is a good chance that no deposit was paid. In this case, the state loses money. That said, how would they catch you unless you had a large quantity and were turning something in just inside the state border. In the middle of a decent sized state (a place like Flint, Michigan or Traverse City) I'd be surprised if they asked for any proof of local citizenship. I imagine that California might have an issue with people from Mexico bringing up stuff through the border. Frankly, I'm not sure if the border agents would do anything about this.

I hear another issue is that some locations don't want crushed cans because they can't tell as easily where they were bought. Not sure how that works.