On the first voyages of the Adventure the smoking area was a small outdoor area off of the main lounge on deck 17 on the port side of the ship. It was a covered but open to the air lounge with seating. This looked like a really great area to spend time in but it was very smokey smelling regardless of anyone being out there (as expected for a smoking area). Currently the Concierge lounge as no outdoor seating on deck 17 that is not the smoking area, and almost no covered seating in the shade on deck 19. If there was a change made from the initial sailings it could be a usage need issue. The smoking area is located below staterooms with verandahs on deck 18, so that may be another reason to change the usage of that area.
The Concierge lounge was selling cigars for passengers to enjoy in the smoking area. Maybe there was not enough profit from this for them to justify the large prime area being used for smoking. That's just a guess though.