I think this is more about the map. It is easier to remember that you have been at the crossing where that triangle street hits the half-circle road than to remember your position in an isomorphic grid, just like it is easier to know you stood next to that tree in a park (a point of interest) than to remember your exsct position in a lawn where every spot looks more or less the same as the other.
Could it be that you learned the chaotic city better because you were more likely to go around on foot and experience little things, rather than just driving to a box store?