Do you drive 66 MPH in a 65 MPH zone? This is hardly breaking the law. This would have been perfectly legal in CAN-SPAM if they added three things: an unsubscribe link, a physical mailing address, and mentioned it was an ad. It probably would have been even more effective.
If you want to stop spam, don't rely on bureaucratic processes to resolve it through legislation. Build a spam filter, or do some simple pattern recognition so you know that the same message sent 100 times isn't a legitimate inquiry to a posting.