In this concluding post of my three-part series on privacy I focus on the harm that could be done by over-regulation and recommend industry self-regulation as a far better way of accomplishing the desired high level of consumer privacy protection. (If you haven't already done so, please read Parts One and Two.) Every data scientist in our industry knows for certain that advertising causes incremental sales which would not have occurred without it. For example, Standard Media Index and Bill Harvey Consulting recently calculated that in the period spanning January 2014-March 2018 in the U.S., advertising added $294.7 billion in sales in the automotive, consumer packaged goods and quick service restaurants categories alone. As a percentage of total sales, the ad-produced sales equated to 19.8%. Another way of looking at it is that advertising lifted the sales which would have occurred anyway by +24.7%.