I was at a conference where several attendees were unable to be present for the group photo... rather than not part of the group photo, they were added afterwards.

I was not put off by them being photo shopped into the photo, I was pleased to have a photo to remember all the attendees.

These days a whole new form of art is emerging that is based on manipulating photos. My brother produces a number of these, they are called "composite" pictures. They are more like art done with a camera than an attempt to record a historical event.

https://schundlerphoto.myportfolio.com/composites

I see no scandal in altering any photo not intended or represented to be a true image of an historical event intended to document that event. In my experience, coming from a family of 9 children, our family photos were intended to convey how we all looked at the time the picture was taken, nothing else. Nothing would have made me happier than to have four or five takes and let someone photo shop the picture, then the repeated shots because one person was not "quite ready" or someone else was horsing around.