Another way to look at it is that the gov could always monitor you via wiretapping, but doing it through centralized data services is easier and cheaper.
One use for this data would be for the IRS, to help determine square footage to see if it's inline with what's reported for home offices
Yes the gov also has this data which is probably one way Zillow gets it. What they don't have is the actual size of your house's various rooms which as I've already mentioned is useful for some agencies
One use for this data would be for the IRS, to help determine square footage to see if it's inline with what's reported for home offices