This thread is exactly relevant to street photography, and not 'off topic' at all. The vague, nameless dread that someone, somewhere will do something terrible to us or our loved ones (or even to perfect strangers) on the strength of our street photography is, to me, risible; or would be if it weren't so pitiful.
As many have pointed out, we are all photographed frequently by surveillance cameras, and there's plenty of other information rapidly (and often freely) available about us and everyone else. The extent to which street photography adds to this is trivial.
Of course it's conceivable that someone sees a picture of a little girl on a web site and conceives a perverted passion for her, but the real question is, how likely is it as compared with seeing another little girl in the playground of his local school?
Still more important, what is he going to do about it? It would need to be a very determined (and quite wealthy) pervert that flew from one country to another, went to a city he didn't know, found the school, and tried to abduct her. The fact that the abduction of little girls (or indeed little boys) generally makes headline news is a strong clue that it doesn't happen very often.
My limited understanding (based mainly on the criminology I studied many years ago) is that victims of sexual crimes are in any case objectified, i.e.treated as objects, not personalities: one child (or one prostitute, or one person of a particular race) is, within very broad limits, interchangeable with any other, in the mind of the perpetrator. Thus, although we may (or may not) worry about girls of any age who are 'provocatively dressed' and may (or may not) deprecate the publication of such pictures, the risk to any particular girl in any particular photograph is the same as for any other roughly similar looking girl.
I have chosen sexual crimes because they create the most shock and horror (and becase my criminal law lecturer seemed to be obsessed with them and used them as illustrations wherever possible). But by the time we get to life in general, I have to ask exactly what people are worried about. One gave the (highly culturally specific) example of medical insurance, and that was pretty far-fetched and contingent. What are the others?
Cheers,
R.