There is no commute, no worrying about what to eat, what to wear, picking up kids, or anything else that consumes a normal person's time. In a way it is kind of like a vacation. You have so much disposable time to spend on hobbies, exercise, or education.
It is very much like being in prison, except that I am not afraid of my fellow inmates. It is strange though, because you don't get to pick your friends, much like prison. I suspect the fellow fobbits are substantially more educated on average than a typical prison population and probably generally healthier physically and mentally. You would be surprised, though, at just how mentally unhealthy many of your coworkers are when you are around them long enough to really see it.
Unless you are extremely ambitious and psychotically disciplined that much downtime grates on your soul. Being deployed for too long can be depressing and you cannot escape a certain amount of emotional isolation. It is also weird having a spouse and children and yet living apart for a year or more like a single person.
The long term consequence of the environment is an unhealthy dose of apathy. If you are too bored for too long you really don't care about most anything. Unfortunately, the environment provides little motivation to care as you are less likely to die in a combat zone stuck on a fob than driving to work in the civilian world.