Even if you don't go to church if you were raised going to church and then stopped, you still might call yourself a [cultural] Christian.

Also being atheist has a bad reputation attached to it for some people, so someone who meets the definition might not self identify as one.

Similarly I expect that's also why there are a fewer percentage of Democrats than there are Republicans. I may have voted down ballot for only Democrats, but am I a DNC supporting Democrat? Not really.

Mt wife consider herself catholic but never goes to the church and live her life exactly like mine as an Atheist (doing drugs on techno parties). For the majority of people is just something they don't really think about and just consider themselves wharever religion just because they grow up in it.

Nominally "Christian" because they like Santa Claus and the Easter Bunny.