Right, but the point of referencing the fact that people generally believe based on the prevailing religions of their region is to give them pause before formulating their lives around an ideology that's typically the product of culture and circumstance, rather than an employment of valid epistemology. A fallacy would be committed here only if said atheist interlocutor said that your belief is false on account of this. Thus, if a person comes to the conclusion that the Earth is round solely based on authority when that same person could easily verify this, regardless of having arrived at the right answer objectively, that person would have no way of actually knowing whether they were right or not. The same person could have easily accepted that it was flat and be convinced that it was true. Consider that all believers of the various faiths think they are right. What's needed is a clear epistemology to begin to uncover the truth, and mere authority and faith isn't going to get you there.