For what it's worth, my family skipped the first formal night on our 5/1 Eastern cruise because we didn't want to get "dressed up" that night. The next day I talked with our waiter who asked "Where were you guys last night for dinner?!!?" When I explained why, he declared: "Come to dinner!! No one cares what you're wearing!!" and I must say, from my experience, there is so much going on in the dining rooms, unless you come in your birthday suit, NO ONE is going to say anything to you, so go clean and comfortable!!