I totally agree with Jim. There are so many natural wonders in Alaska that you will miss by simply people watching. It is easy to incorporate good food into a sightseeing tour. At the end of the tours there is almost always time to find a place in town to sit, relax, and have a drink.
If you check on the excursions your ship offers, many of them will include grilled or smoked salmon dinners, dungeness (sp) crab dinners, etc. By doing one of those, you can view some spectacular sights and also dine on great local foods.
In Juneau we took a floatplane to the Taku Glacier Lodge. It was fantastic. The food they served at the Lodge was delicious and the owners were super friendly. It is pricey, but worth every cent.
In Skagway we took the White Pass Railway to the summit and then a bus back. The bus stopped in Liarsville where we had another delicious meal.
I hope you decide to enjoy the uniqueness of the area. You won't regret it!