The real answer to this question is the Public Land Survey System, which is how most of the land in the United States is divided, with many exceptions. Mostly states that were under direct control of other countries, such as Louisiana and Texas, but even those use PLSS for parts: https://en.wikipedia.org/wiki/Public_Land_Survey_System PLSS works best in states that are flat and open, hence why Kansas especially follows a grid system so rigidly.
This is a good example of the grid system working despite being bisected by a major river in Nebraska: https://www.google.com/maps/@40.8158497 ... a=!3m1!1e3 But notice how when you get further from the river and the terrain becomes more undulating, the grid system stops. Or look at North Dakota and see how the grids taper off as you go west, finally disappearing at the badlands of Theodore Roosevelt National Park.