Nosfer said: "The lighthouse itself, yup cashing in on that. And rather dearly, too. It's a pretty penny if you want to be there after dark."
I know that the forum has had ethical debates over this type of thing. Personally, I don't have a problem with it. If people want to go to a lighthouse/museum and chase around whatever…fine. If that helps keep the doors open to the public, then so be it.
@Judy – Hopefully you had a chance to watch tonights (Oct 20) GH episode (S06E19 The Chopping Block). It basically had everything that we've been discussing…
In the basement, Steve and Tango discover that shadows are tricky indeed. Apparently K.J. is walking outside and casting some weird shadows. To Steve and Tango's amazement, they have an "eureka" moment and discover light refraction. Yes, light hitting old glass at weird angles can throw shadows all over the place. Shocking. Some of the shadows, like those seen in the St. Augustine episode, seemed quite solid as well. Too bad Steve and Tango didn't discover this light refraction thing a bit sooner… 
Then we move on to Britt and K.J. stalking a shadow in another part of the building. As they walk around, you can literally see the lights of the town outside the windows. Doesn't matter. Britt thinks he sees a shadow moving around. Does he consider what happened earlier with Steve and Tango? Not in the least. He intently watches the shadow and takes off after it. Again…literally chasing shadows. And I still don't know what the objective is with that. Perhaps he hopes to use a nail and nail the shadow to the floor like in Peter Pan. In any event…this is exactly what we saw in the St. Augustine episode, people running towards shadows without a care in the world that they just might be normal shadows as opposed to paranormal entities.
Lastly…you asked about the lighthouse keeper (I could be wrong, but I think he was just the manager). I believe that his interests were honest and well as his reactions. Only afterwards did he figure out that he could cash in. Tonight's episode with the building manager…another story. J&G could have played any sound and he would have considered it paranormal. They literally could have said or shown anything and he was going with it, matching it up with whatever personal experience, and making plans on how to market them to the ghost-touring public. Maybe he saw the dollar signs…maybe he was ordered to, I'm uncertain. But whatever the case…that guy was all about turning the paranormal into cash. Again…I'm not against that necessarily.
Just saying that the lighthouse guy just probably responded to requests for ghost tours and turned into a cash cow. Keep in mind, at that point GH was still primarily investigating private homes as opposed to businesses. The "GH/Ghost Tour" effect from being on the show wasn't clearly established yet.