One of my company first Sergeants had this to say on the subject of military discipline: "We're here to defend democracy, NOT to practice it!"
Even though I may not have been pleased to hear it at the time, he was right all along. Accountability, serviceability and uniformity are the hallmarks of military order. A military without order is just a rabble.
Not that I wish to go back to living as a soldier now, but having done it, I have to agree that most of the rules are necessary to maintain order. How this can be applied in times of changing social mores in the civilian sector will always be a moving target. Sexual relations between members has always been problematic, it's not new.