The person who submits a photo of your ancestor to FindAGrave, FamilySearch, or any other site may potentially know absolutely nothing about your ancestor. It is very possible they found the photo while browsing the internet (often obituary pages, but not necessarily), saved it (with no citation), and uploaded it.
Consider a reverse image search at Google to see if you can find other locations where the image is posted–perhaps by someone with more knowledge about your ancestor or perhaps where the image was posted originally.
One response
So, so true. Some of the pictures that I uploaded have been copied and saved by other people on FamilySearch, attached to other people who I am not sure are related. I have never been contacted by any of these people to get permission, to ask what I know about the my ancestor, or for any other reason. Personally, I’d be leery of using anything I find there unless I can personally verify it.