I hate all ghost hunting shows. Maybe they get people more interested in the paranormal, that's about it though.
They are what got my wife interested in investigating, and myself, as well, after watching over her shoulder for nearly ten years. These days I find Ghost Adventures very useful as a showcase of technology, as well as highlighting venues that I actually have a chance of investigating, myself, in many cases. Zak is based in Las Vegas, a 9 hour drive from my home, and it also means that G.A. is constantly investigation locations close to me, as well. I have been to several that Zak has covered and found them interesting and worth my time.
I am familiar with production TV. These shows are actually loosely scripted and the theatrical component is very high.
They are entertainment, not science or even serious documentaries.
I am also constantly amazed that some so-called "professionals" still have no clue as to how some of their gear works, and can't even tell the difference between a thermal butt-print on a wall left by a member of the team, and real paranormal evidence (Destination Fear reference, Zak is Exective Producer).
I have only been investigating for a couple of years now and still find value in these shows. I rarely catch everything after only one viewing. I expect a comedy of investigative errors, but there is still much to learn from observing what others use in various situations, and how they use it. I maintain that these shows serve a purpose and are, at the very least, entertaining.
What I can't stand are the re-enactment shows. I still haven't seen an Eli Roth episode that I can sit through for more than two or three commercial breaks. There is just zero tension or fear. Totally flat for me. Meh.