I understand the fear of being tracked down and the need to safeguard children. The additional stress of not being able to control your privacy must be huge OP. I feel for you.
I guess it must be most likely to be dangerous in situations where people have simply left their abusive partner, but have not done a full relocation, supported by police, to another region or county. This must be far the most likely situation that happens most often. OP is right, there are ways they could be tracked down by public images.
For example even if I had my children move school but my ex knew the family were still in the area, and was an unhinged nutter trying to track me down, it's not beyond belief that he might sit at his computer and search all social media of recent local events suitable for families and children of the age of our kids during the weekend or holiday - lights switching on, village funfairs, new attractions opening. It's still kind of unlikely he would find us that way but it would add massive fear to the victim's life.
I do think local businesses could be asked to share non identifiable pictures only. You can show the happy crowd at your fireworks or the audience at the dog show with a little blur on the lenses. That wouldn't hurt. Many businesses are already recognising they shouldn't show loads of identifiable images of children and voluntarily adding blur or stickers.
In the future AI image searches will get even better so people will be able to purchase software that scrapes all public video and matches it to a picture of someone you want to find. It is scary.