Comment by korkoros

Squares have a contiguity problem: does a square in a grid have 4 neighbors (rook contiguity) or 8 (queen contiguity)? Hexagons do not have this problem. All neighbors of a hexagon share a full edge, not just a vertex. All neighbors of a hex also have their centers equidistant from that hex. A massive number of spatial problems turn on neighborhood definitions, and hexes are almost always a better representation of reality than squares.