It is more or less trivial to find someone's home address now if you try at all. Thats my point on duplicated data in hacks.

It really depends and I often struggle with it. How do you do it?

The German Melderegisters, for example, are now far more interested in the stated reason for your data request than they were ten years ago. (Which is a good thing!)

Many things that are trivial in theory, given the right conditions, etc. are anything but trivial once you actually try to do it.