Some folks cannot wear head phones for an extended period of time which makes me very happy I have an office. Plus, noise canceling head phone make me dizzy even if no music is playing. I'm pretty sure that's not unique.
It probably isn't. I can wear my in-ear noise-blocking headphones for about two hours until they become physically uncomfortable. Over-ear headphones are fine for up to four hours. An open office is just not a workable environment for me.