My agent once told me that only one percent of writers ever get to quit their "real" jobs. For the remaining ninety-nine percent, we still need to keep that day job and somehow manage to strike a balance between our "real" jobs and our "dream" jobs.
Unless I'm home, I write primarily at night when the obligations of the day (real job, house, kids, animals) are taken care of. I know a writer who can sit in the middle of a busy cafe with people coming and going and write his heart out. I admire him tremendously for that, but I can't. I've never been able to write when other things can so easily distract me. Wish I could. Despite the limitations of time, I've still somehow managed to eek out four manuscripts (two already under contract) in three years. Not a bad run, if I may say so myself.
Writers rarely have perfect circumstances under which to write. The most successful authors (the distinction being an author gets published), are those that are disciplined enough to force themselves to carve out an hour here, a weekend there, and get the job done.