On TOS, Kirk referred to himself as a soldier. That was not a writer's mistake.
About the idea of the ship having a so-called "Office Environment," no, it is not. In the episode "A Private Little War," Kirk--tense and frustrated after Spock had been shot by a native--barked at his bridge crew:
"I did not invite a debate!"
The crew (Scott, Chekov, Uhura, et al.) respected his authoritative position, as is the nature of a military command structure. Kirk apologized (they are his friends, after all), but his natural response was to shut down opinions he did not necessarily ask for, because that is the kind of training he--and all Starship captains--received. That is far closer to military relations than any loose, civilian kind of interaction.