The issue is that these deals and tricks are always changing, and their half-life is related to their access; if a trick is both profitable and well-known it likely won't exist for very long.

Nowadays, most of the best knowledge of tricks in this domain are private anyway. I enjoy travel hacking and the community around it, but it's ruined effort if I post an interesting hack in a public forum (ie FlyTalk), only to have some blogger broadcasts it, thus alerting the relevant company and ending the deal.