I think it's an addiction to a hobby. For myself, I'm up at 625am typing on a Compac sailboat specific forum which says addiction to me. The person I purchased the boat from would fall closer to a non-addict to the hobby as the boat was beaten like someone who looked at her as simple a vessel to enjoy for the moment and nothing more. I think we look at our boats as much more, that's why we spend hours talking about various projects and upgrades.
I have a very addictive personality, be it too many beers, running my body into the ground doing triathlons, and now obsessing about the day I can push off the dock with no return ticket.