Ghosts are catorgarised under 'superstitions' and superstitions are make beliefs. Word has it that ghosts are 70% afraid of humans and humans are a mere 30% afraid of ghosts. Ghosts are generally a 'game' that your mind is playing with you, and when you're afraid of ghosts means you're on the losing side. Whatever happens, like doors creaking, seeing things in the mirror, etc. These incidents all have a logical reason behind it--definately not ghosts. It's just your mind playing tricks on you.

If evil was not punished, people won't learnt their lessons from the bad things they have done, and will also not know the harms that they have done to affect other people. Good people will also not get their justice and might even be influenced by these bad people as they can get what they want by doing bad things and not get punished.

So, I think evil should be punished.