Uh, because if I played all the music and movies I enjoy at work I'd get fired.
What's your job? Ditch-digging? Because other than that I can't believe the same thing doesn't apply to you.
I'm a student at a Christian school. My music is all secular, but would not offend anyone there (Barenaked Ladies is a far less raunchy band than their name suggests).
If you have a job that is in opposition to your tastes, perhaps work for someone else?