I understand people are scared of things. But without sounding like an ass, i don't understand, and don't personally care for anyone who would not take part in something due to a fear of an immaterial thing.
It's a haunted house. It's halloween. You went there because it's the time of year of scary things. You went to get scared. Fear can be an exciting emotion when you know it's safe and controlled.
For example, people are scared of Pennywise the clown in IT. Ok, he was an actual monster clown who killed children. If there's clowns in this place, it's just some dude in a costume who's gonna take his mask off in 20 minutes to go drink a soda and take a pee, just like you. It's not real, you know it's not, so i don't understand the big deal personally.
It's safe, organized, and controlled. It's there for your entertainment, you decided to go there, so enjoy it or don't complain and leave. Go home watch America's next top model and forget the fact that it's October 31st.
That's what i'd say, and have said.