Then fred takes the mask of the ecto 1 and says it was old man cribbins the whole time. And the ghosts were just sheets on strings. And the gatekeeper was just elitist goth musicians.
Somebody is obviously trying to cover all the bases. That’s just good thinking. If ghost are real, they get zapped. If they aren’t real, they get to chase a group of adolescents all over the place for about 20 minutes before said adolescents figure out it’s not a ghost for the umpteenth time.