I agree that the pokemon spawn conditions being tied to population density is pretty idiotic. If you live out in the country, there might be literally miles between each pokestop, and there's no way anyone's got time to go to these several times a day to get a reasonable amount of pokeballs, And pokemon spawns are often a mile or two in between as well.
If the game really wanted people to move around, they should make rare pokemon spawn far from civilization too, to make people do something as crazy as go on a mountain hike for example, or a walk in the forest. Idk aboutother areas in the world, but I usually have edge coverage in most forests and mountains, so that's sufficient for the data transfers required by this game.