We are also not used to paying gratuities, as is standard on a cruise, as we like to tip the people that gave us good service. Reading the small print of all the paperwork that Princess send out, when we got on the ship at Anchorage and before we left, we went to the Customer Service desk and opted out of the 'gratuities' option. You cannot do this after sailing.
We didn't bring anything for the 'formal' night as our focus was on the scenery. On their 2nd 'formal' night we saw 2 humpback whales breaching up on the top deck, while we were enjoying a glass of wine, which was far more exciting for us than sitting for 2 hours in collar and tie in the restaurant and missing it!
Although we were booked on anytime dining we ate mostly in the buffet restaurant, which was excellent, mainly because we were constantly looking for whales and wildlife.
We enjoyed our cruise, especially the whales, sea otters, eagles and seals that we saw!