Submitting your site to Hacker News can yield insightful comments, new users, and potentially result in an investor taking some notice. That isn't the same as deliberately pitching investors, though. I don't see how charging a specific fee for a specific service in an up-front fashion like this is predatory. A barrier to entry such as the fee charged probably makes the quality of applications and applicants better. That being said, at this point, I can't imagine myself paying for such a service. I prefer to network the old-fashioned way.