The reactions of atheists (or anyone else) to seeing a large family can vary widely and depend on the individual's personality, beliefs, and experiences. Just like with any diverse group of people, there is no single or universal reaction.
Some atheists might not have any particular reaction to seeing a large family and may simply view it as a personal choice made by the individuals involved. Others may admire or respect the family's decision, recognizing the importance of family bonds and the joy it brings to them.
On the other hand, some atheists may have concerns about overpopulation, environmental impact, or issues related to resource distribution and may feel a sense of worry or disagreement with the idea of having a large family. These concerns are not necessarily related to atheism itself but might align with certain philosophical or ethical viewpoints some atheists hold.
It's important to remember that people's responses to various situations, including seeing a large family, are influenced by a wide range of factors, including their personal values, life experiences, cultural background, and individual perspectives. Therefore, there is no one-size-fits-all answer to how atheists or any other group might feel in this context.