Sherry D, I don't think you're missing anything at all.
We all have to be aware and practice 'safe internet use', but I do think sometimes a little hysteria takes over.
Unless real names and addresses are used I really don't think anyone can positively identify anyone else. In extreme cases there may be one or two who 'think' they know who someone is but unless and until the person concerned confirms it that's all it will remain.
As for the teacher who used this website as an example, well, I think more harm than good's been done. I'm all for informing children and 'safe internet use' but this infomation has obviously scared them!
I openly challenge anyone to identify me (and I've posted more than enough information to be able to identify me over the course of time on these boards, you just gotta find it
). If anyone can, please pm me - DO NOT do it on an open board, and I will disclose here on this thread whether or not anyone has been able to do so. As I have nothing to hide, done nothing wrong and nothing to be ashamed of I don't expect it to change my life even if I were 'recognised' ............................. but I won't be