Mark that was tongue in cheek but there are people on all kind of forums that just do that, scouring sites to see where people live and what kind of equipment they have.
I also do astrophotography besides 4w driving and it is an very expensive hobby so i am very careful on astro sites to not name all my equipment.
There is also the problem of insurance companies keeping watch on forums as this, for illegal mods, so they can disonour an claim when someone has an accident.
This is made very easy when they can sort drivers by name and/or vehicle.
As you may have seen on other forums, people have been dobbed in by others after boasting about their mods
For some astro photo's go here -->> http://martinsastro.net