"Because it belongs to the dead guys."

Beetlejuice made an exasperated gesture. "Just imagine that your hom--ship. You die in your ship. And stick around. Then some other bozo comes around and changes all your stuff around. It's annoying the hell outta you."

He raised a finger. "But, they can't see you. So they have no idea. And they also don't care, because they bought it something. So, sometimes ghosts need a little help from someone who can be seen."