Summary: your home and work locations represent a simple "hashing function" that will allow firms to uniquely identify us. This information on the surface wouldn’t seem to represent a privacy risk but is and it's becoming easier for third parties to collect with the proliferation of location based services.
Ignoring the privacy issues, I think universities would be an exception, as many student/staff live on/near campus. I suspect people who work from home would make up a disproportionate number of the collisions (as they reduce two dimensions into one) - so perhaps their is privacy in that.
