You can be very religious and not go to church. You can be religious and not belong to a holy roller church like the SBC.
Amanda Marcotte needs to get out more. Just because she doesn't know many churchgoers in her circle doesn't mean there aren't many outside it. In fact, in my age bracket and in my part of the country, in southern Oregon, there are few atheists. The older you get, the more important religion becomes in your life. I truly believe it is a natural state of humans to be more religious after they have had much life experience and have gone through deaths of loved ones and some tragedies in their own lives. I have gotten to the point I have little use for atheists because they are just as bad as the worst religious types. They are two sides of the same self-righteous coin. They are so sure their point of view is right, but they can't be absolutely sure, of course.
It really isn't natural to be an atheist. You have to work very hard at maintaining the facade of being rational, of depending on science for all the answers. Science doesn't have all the answers and certainly not the answers that religion provides to its adherents.
The problem with atheists, of course, is they completely misunderstand the purposes of science and religion, the two of which are not incompatible. They have the same problem that fundamentalists have (most religious people, including Christians, are NOT fundies).
One of the major purposes of science is to explain the HOW of human existence, HOW we got here.
Religion seeks to explain the WHY of human existence.
There is NOTHING incompatible between the two. They are two completely separate fields. That's why many, many scientists are very religious, even devout. They see no inconsistency between the two.
This is something atheists, in their self-righteousness, haven't figured out.
And since most of them are younger, they won't figure it out until they are much older.