I was at a business meeting recently and one of the executives mentioned he read my blog. He confessed he too was an Atheist, but they still did Christmas and Easter, of course, for their kids.
The mom of our son's friend said she was a non-believer, but raised a Jew she was in turn sending her kids to Sunday school, “for the socialization aspect,” i.e. it's what everyone else is doing and has done.
Another mom, of our daughter's friend, also admitted to questioning her belief in any god, but was sending her kids to church to learn morality, values, as if she doesn't know what the right ones are, or is unable to establish an open dialog with her kids on both abstracts herself.
My in-laws recently threw a $15,000 Bar Mitzah for their son, though neither go to temple. Ever. They claim to be agnostic. They do not believe their child is now a man at only 13. And tomorrow, and the next five years (or more) to come it's likely he'll still be living at home being cared for.
Most people practice the religion their parents do by blindly passing on their family traditions from one generation to the next. Self-proclaimed Atheists or the closet non-believers who practice religious traditions perpetuate religious ideologies.
Tradition has very long talons with a vice grip, and sustains religion. Don't believe? Then don't pass religion on. Perhaps it's time to start breaking some antiquated traditions mired in ideology you no longer believe, and develop your own traditions that reflect the beliefs you'd like to pass on.