That's an interesting questions, because it looks like the network has gotten some decent media coverage (Inc. magazine) and the person behind the network is out speaking as an expert on angel financing, which will makes him look credible.
It's easy to say "buyer beware", but if the media and credible organizations are inviting the network's founder to speak as an expert, then entrepreneurs will be pulled in. Word of mouth online will help reach some people, but certainly not all.
To answer your question ... it's obvious that on an individual basis, entrepreneurs should not participate if worthwhile investors are not attending the events.
Collectively, entrepreneurs might benefit from a media campaign trying to get the business press to write cautionary columns about paying to pitch. It's an interesting story and if packaged right could catch some interest that would help educate entrepreneurs about the risks of networks charging to present.