Look Vedic God is different from God of Bible, Quran or Purans. Most people when they refuse to believe in God are actually refusing to accept superstitions in name of God as propagated in name of religion. The anathema of West against God is only for the God of Bible. This is justifiable because God of Bible has many contradictory properties and at times acts like a mortal human being. But Vedic God is different. In fact God may not be the right word to denote the Vedic concept of Supreme.
The Vedic concept is much more intuitive and natural – that there is a source of unchangeable laws of the world that govern this world and us. Physicists may simply call it Law of Nature. Now a smart Vedic follower adds a dash of positivity into this and says that this source of unchangeable laws is acting in a manner that we can enhance our happiness through right actions. We are neither left in lurch like orphans nor allowed to escape fruits of our action. So there is a well-founded optimism that the laws of nature ensure justice and support. We believe so because we see this very obvious in world around and in our innate tendencies.
But someone intellectual who was nurtured in a society that had completely different notions of a Supreme entity – an anthropomorphic entity, or a moody emperor, or a magician etc – may find such a God hard to digest. And it would be difficult for him to dissociate word God from this meaning and give it a new meaning in perspective of Vedas. For example, Arya is a very noble word. But in Germany, people would somehow try to link it with some sort of racism because of the Hitler episode. These words trigger certain emotions due to their previous associations and hence difficult for many to appreciate any new meaning easily.
Thus, atheism is a natural and rightly-directed aversion of a truth-seeker from what his mind considers as unfounded notions. So in being atheist, he or she is STILL acting as a loyal follower of Vedic religion.
In other words, a truth-seeking atheist or agnostic or even a superstitious believer in some other notion of God is STILL a Vedic person, if he or she believes in these notions honestly after whatever experience, expertise, intellect that they possess at a given moment in time.