Playing devil's advocate for a moment, No property or person is being harmed with spam. Time is wasted, yes. But no crime is being committed in the normal sense of the word. To compare spam to thievery, blackmail and extortion (where their is a removal of property of threats to a person) is not a very good analogy and I think taking things a bit too far. It's closer to aggresively handing out flyers on the street and possibly a case of harrassment.