I always eat lunch at a nice restaurant on land, then wonder over to the ship when the lines for embarkation are gone. My Cabin is always ready, my luggage is in the cabin, no carting my carry on around. You are going to eat on the ship for 7, 14 or however many days your cruise is. You may or may not return to the port you are sailing from; therefore, you may never have another chance to eat a great local meal.
Everybody has different tastes, so I am not being judgmental here, just pointing out another option.