For me, it wasn't. My family has been in New York city for well over 100 years... Irish heritage. From an early age i didn't buy the story of Christ, let alone the catholic thing.
I remember asking my grandmother - if Jesus knew he was god, then why is any aspect of the story impressive?
The best she could do was to tell me "its just important to believe" which of course just doesn't last. But she never raised her voice or made me feel unaccepted in anyway. I was about 10 at the time, and never gave the god question much thought until i was 23 or so. I was irreligious but believed there must be something... then i met a woman who commented "unless god means a timeless, disembodied creator of the universe, then you're just playing word games". Ive been an atheist since.
Despite the religiosity of my mother, and her mother, i didnt get much guff for my questions. And i never felt in anyway disadvantaged for not believing.
I'm privileged to be an atheist in NYC... its really not a big deal in my experience.
Whenever the subject comes up, i freely state my disbelief. My biggest interest is how anyone can believe, and as far as ive been able to figure, its a combination of wish thinking, tradition, lack of consideration, or fear of death.
I'd enjoy hearing about other people's experiences.