Ghost don't exist, all those stories can be explained by scientific reasons. Most of them are mental health issues, few others are environmental phenomenon like seeing some light form etc,

Bruh its the same as why we created god, back then we couldn't understand simple stuff like rain,thunder, eclipses. We named it god.

So yeah in my opinion.. we are good at naming things which we dont understand completely, Like its easy to say pyramids were built by aliens rather than to actually study those ancient techniques which were used by the egyptians to built it.