No, being an atheist shows that a thought process is used to weigh facts on both sides of the issue and come to a conclusion. It's similar to how some people, even unknowingly, choose a religion.
This Sunday, check out the attendance at your church. Do this every Sunday. Also, check the attendance for the evening services on Sunday and Wednesday. (the most common evening services for churches) Except for small churches, you'll discover that the evening services are lightly attended: less than half of the Sunday morning services. These are the people that have weighed the evidence of their faith and determined that the church required their support more than just Sunday morning. What of the members that don't attend evening services, but show up every Sunday morning? Some MAY attend services elsewhere in the evening, but that is rare, requires analytical thought, and compares how others interpret and preach the gospel. Keep records. I'm certain your church does, so use them. Now, compare the Holiday crowd. Thanksgiving, Christmas, and Easter services have long been the butt of the "Where's the church that we go to" jokes for years, but it's true. A church with an average attendance of 200 parishioners a week will find those numbers swell to 3-500 attendees. Those attendees rarely think and make the conscience decision to go to church. They may just be going because that's where they send their kids on Sunday morning so that they don't have to deal with them, but attend solely to keep up appearances for their kids. The kids are too young to question it, usually, and eventually leave the church.
The key difference between an atheist and a true believer, though, is which facts they accept as true.