In politics, the act of drawing, reviewing and re-structuring district lines for voting purposes to ensure that like demographics are aligned is a common practice.
These lines appear bizarre when viewed on a map due to the non-uniform nature of redistricting. Why don’t politicians just use ZIP codes? Politicians learned many years ago that zip codes are not demographically sensitive.
While it is fair to assume that there are some similarities with you and your immediate neighbors, within a few short blocks there are often stark contradictions across virtually every demographic data point.
ZIP codes are not even real areas. They are, in fact, a series of delivery points. Even when treated as areas, they don’t have the density to relate to urban communities.
Somewhere along the evolution of display advertising the “ZIP code” in its assorted repackaging forms became the standard for location and demographic based targeting.