I can appreciate their ability to think outside the box, but when you are using your competitor's resources to promote your company you might be crossing a line. It's a subjective line of course, but I personally find it unprofessional and makes me suspicious about the methods used by such a company to obtain those 500,000 views in a weekend. I'm not anti-marketing, on the contrary I'm very much pro marketing. But what they did is not far from the offline equivalent of spamming your competitor email list.