I always thought this was odd too. I'm glad the crew has a place for a little exercise, fresh air, and to just relax, but it must be awkward trying to enjoy yourself and get away from the passengers when they can literally just stand there and watch you. Also if
DCL is like the Disney parks I'm sure they stress the "Disney look" but I can imagine that's uncomfortable if you're hanging out in a bathing suit in full view of everyone, even if you're not on the clock.