Most ships have a bar, with a piano. The scenery of the Inside Passage, the company of my fellow travelers, and a good book were all I wanted. But passengers who want dancing, music, gambling and so on will be disappointed. Travelers are also expected to plan their own itineraries in port. That's great for independent travelers but won't work for folks who want a pre-planned guided vacation package.
Tourism offices can help.
You may take pets for a walk while the ship is in port. You will want to make your plans early if you are traveling on the ferries during the summer, the most popular months, especially if you want a private cabin. Most of the ferries are wheelchair-accessible and have elevators. There are baggage carts to get belongings on board. Baggage is limited to 100 pounds per person for walk-on passengers.