I believe listing my location is an all or nothing thing...
...if listed, it is public to lurkers and some people don't want to disclose it.
For instance, I list my hometown only because I had a very abusive (to all her family one way or another) ex who is a true sociopath. Chances are she could be reading this very post by lurking since it is common knowledge to her that I frequent this site. I could go on and on and stoop to her level and bash her with detailed truth on how crazy and disgusting she is...but you get the point. In summary, she is a very dangerous person.

Sure there are other means to get someone's address...but I limit this one.

Fellow chrome domes who want to have a beer with me know how to get a hold of me and I them.

I think a good question is, for those who haven't updated their profile since registration...did they just forget to do so?