Yes on the bathrobes. I don't want to take mine either.
The concierge can make priority reservations for you in the alternative restaurants (and you can book them for every day on the first day if you'd like); he can get you priority tendering so you can get to your shore excursions; he escorts the first group to leave the ship at disembarkation, as soon as customs clears the ship (or if you don't want to leave that early, you can stay in your suite and leave later in the morning--your choice). Hopefully I haven't missed anything.
We used the concierge to make dinner reservations only (and we changed our minds a few times during the week, without problems).
Hope this has helped a little.