Why do people their pet boating?
You have a boat. You have a dog. You don`t have instant overnight dog care available. Not all dogs tolerate kennels (we had an escape, plus 2 expensive life threatening illnesses in kennels). You want to be able to overnight onboard when you want. So, you take the dog with you. To make it work, you do some training and preparation.
Result? You are never kept off the boat on a prime weekend for want of a dog-sitter. It`s not perfect, few things are,it`s a balance thing,though quite a few dog owners would take the dog along even if they had care options, and a lot of dogs would support that too.
Our dear girl, a 30kg Shepherd/Kelpie,remarkably active nearing 13 years, her health under a real cloud,came to us age 4. We never introduced her to the boat, which came later anyway, and the first one lacked walk around decks which are a plus for a dog. When we lose her,any newcomer will go onboard as a pup, and despite a lifetime of German Shepherds, we may seek a smaller more "portable" breed,eg. a miniature Doberman Pinscher.
But it`s equally likely we`ll spot an orphan big enough to double as a bear,and take that onboard. BruceK