It honestly boggles my mind how anyone can believe in ghosts or negative energy or karma or anything like that.
Once you've seen the other side of things. It's hard not to believe.
Also not all activities are "ghosts" in the sense ppl think of them as. You have to understand the realm of timelessness, or what Nichiren Shoshu Buddhist have pegged as Kuon Ganjo: (Time without Beginning). Basically TIME in and within itself is infinite yet is put a spiral, existing as both past, present and future all at once. Therefore where you stood say at age 4 as a kid, guess what? You're still there. You are you now but you're still there. Any relatives etc, who have died are still alive, not in our physical realm of linear time, but they are still alive, while we have moved forward.
Thus when you hear of people who speak to the dead in places. Not always so. Often it is you physically taking up the same space as the people who died in our worldline as it exist in the present, but the energy left behind at that point is still there. If you are an esper, (meaning higher sensory perception) and even moreso a spiritual person... you could in fact FEEL and even hear those people and have discussion. They would not however know they are dead, to our timeline they are, but they are not. This extends to the multiple yous and me that are also out there. But that's a whole other discussion and I'm still recovering from the flu, so... But yeah. I was born 20 seconds ago, I AM right now, and have already died. I just haven't caught up to the point (in this realm) where I'm dead. Yet I've just begun.
Just because you think stuff like this is mumbo jumbo, doesn't make it any less true. In this way there are similarities between various religions and Shaman's have been on the Vision Quests from day one.