Infringe much??? How did you get caught infringing twice in seven months by a single law firm?
Sending a copy of a complaint is a very common litigation tactic. It is usually a final warning shot. It is also a strategic move to later support a request for the judge to order that you pay their attorneys fees. They will say they did everything they could to resolve the claim without litigation, including sending you a sample complaint, and you made no offers to resolve it. That being said, them sending the complaint or sample complaint does not necessarily mean they will file it.
Higbee files a lot of lawsuits for Sadowski. He has filed a few for RM Media too, but not as many as for Sadowski.