Why are people scared of ghosts?

because ghost are scary..

They are scared of the unknown.

one of the academic answers is: ghosts are the unknown things. they are in the trilight zone between the dead and the alive. we living people have the death instinct. we are scared of death. we cannot make sense of death by using our language and logic. (if you have the chance to see someone dying in front of you, you will understand what i mean.) death remains mystic, even for scientists and atheists. ghosts evoke this anxiety of the unknown world of death. (there is a technical term called "Oject petit a") part of us is connected to the unknown world that is not included in our language and logical thinking. therefore, you cannot utter logically why ghost is scary; all I can say is that it is an inate feeling. It is much deeper than language and scientific explainations. you are born to fear ghost because death cannot be fully understood.

Because you never know what their capable of. They can either be a good ghost or a bad one.. and if it's a bad one it can do some strange sh*t

Because people believe in fake stuff like "the boogy man".
Seriously i dont get it. Its easy to speculate that well, these people are uneducated or whatever but i have heard people of all educational backgrounds - from high school drop outs to college grads who believe in this stuff.
I would say there are several reasons that can lead one to believe in this. Some might have grown up around parents or family members who believed in ghosts and taught them that they were real, thus they believe in it as well. Some might be misinterpreting strange dreams or sleep patterns that they are having as seeing some sort of ghost or having some sort of out of body experience.

If they believe in them then they would be scared of em'

The unknown. Ghosts are just looking for friends, i have seen them, nothing to be scared of.

They're worried they might turn them into ghosts.

becus the gost is a scary creture they liek to mischif and commit fraud.

som,etime goest will try to eat u and smoek your sigars, but yousehully they will only opin cabnet dors and go boo!

Because they scare the ｆcuk out of people. Wtf? you're not afraid of those creepy fcukers?

Korean and Japanese Horror films are the the most terrifying, haunting and creepy in the world.

Forget about Freddy and Jason, those two are ｆｒiendly little
faｇｓ。Ｔｈｅｙ are actually cute little virgin 20 year old women compared with real horror.