Short and simple:

And the reasons:
We are not "the common hunting party" like on TV. Our vision is to help people who have a real phenomenon in their surroundings. We collect evidence and documentation to help people out of a perhaps grueling situation. Evidence and documentation, from our experience, helps solving the task: Finding the right methods to obtain peace for the witnesses and obtain a normal life.
It is important for us to have 100% ownership of the task, and the task is solved in terms of methods we have found  the most effective. Therefore we assess that  "spectators" will hinder our task.
Another aspect is confidentiality. Under no circumstances should information about our task be known by others, unless the witnesses have expressly agreed. Who will put their house and life on display for a "Halloween night"?

In conclusion:
No, we're not grumpy old men (!) It is important for us to keep 100% professional and sharp on a task that at times approach military precision.
We find the team does this best alone.

Will you hear about the paranormal, which has been "declassified", so keep an eye on our Facebook page where we sometimes advertise lectures.