Had it been me, I would have had a photographer there too. Look into the charity “Now I Lay Me Down to Sleep”. They specialize in doing shoots of babies who were stillborn, or expected to pass right after birth. These pictures are all parents have of their sweet babies. The lives (even if only in utero) of those little ones needs to be documented just like you would any other child, if not more so. If you don’t have pictures, and small keepsakes, it’s like having nothing to remember them by.
Why do you think is wrong with having a professional photographer take pictures of a sweet little baby?
Your question, “ I am curious why there’s a professional photographer at every meaningful event”
My response is, because it’s a meaningful event and people want to capture those memories.