Ghosts, do you believe?

I have had my fair share of ghosts, truth is the ones I saw at my grandmother's house has led me to believe in them more. Then again, being attacked by one is not pretty either, so to say I am scared of a ghost, there are some that are bad and some that are good, I think I prefer the ghost cat at my parent's house over the ghost at my grandmother's old house in Oklahoma

The existence of ghosts seems impractical, and the I think personal experiences with ghosts are more likely the result of mental conditions (i.e. or conditioning, people who believe that a place is haunted tend to experience hauntings) as opposed to supernatural. Case and point, MTV ran a short lived reality TV show called Fear and various contestants would visit "haunted" places. Even though the events which happened in these buildings were completely fabricated, contestants still experienced ghostly encounters with spirits that were honestly born from the minds of writers instead of some tragic event.

But if they really do exist, considering the following...

Dinosaurs have existed for millions of years and suffered through multiple mass extinction events, why hasn't there ever been hauntings involving dinosaurs and various other extinct organisms which existed much longer than human beings? Dinosaurs existed for over 6,000,000 years and human beings at about 200,000 years. That puts the likelihood of dinosaur hauntings at a rate of 30 times more than hauntings involving dead humans. Regardless, to this day, I have never read nor witnessed pteranodon poltergeists.