Are you scrubbing Exif metadata on all these? I spot-checked a few and there didn't seem to be any embedded. A surprising number of people have no idea that their mobile phone may embed GPS coordinates in images they take with it.

I think most social media sites do this by default but I wish they were more selective about it. Okay to scrub GPS location if present but copyright/photographer/exposure details, etc, are all helpful and should be kept if at all possible.