Honestly, people are just trying to share pictures and life updates with friends and family. At least, the kind of people the person you replied to is referring to are. It wasn’t something I thought much about until my wife (who is a teacher and more attuned to kids and privacy issues) mentioned she didn’t want our kids to have a ton of people posting pictures of them everywhere. Once I sat and thought about it I was in complete agreement but it quite honestly hadn’t crossed my mind before that.