Still very walkable and nice for kids.
Price for these houses is ca. $100_000 (some little over, some little less).
http://maps.google.com/maps?q=&layer=c&cbll=55.7224384,8.533...
[0] https://en.wikipedia.org/wiki/Disposable_household_and_per_c...
A big part of this is long term cultural: medieval towns (and even much older) were all clustered very tightly into blocks with city walls against attacks, those slowly evolved into the vast majority of the towns & villages in Spain today, and have left a culture where flats and dense city centers are the expected norm and the primary model, even for towns surrounded by empty space. You can easily find small towns of apartment blocks and tight wall to wall houses in windy city centers, of just 1000 people, surrounded by fields for miles.
The Spanish would argue that surburanism is generally less enjoyable (walkability, community, socialability) and less secure (houses are easier to rob than non-ground floor flats) while dense apartment/etc living is better value (less land cost, shared maintainence in apartment blocks) and provides better airflow/heat management & opportunity for balcony views (attic flats etc).
It's not like the land was wasted with parking lots. It's just as generic a desert setting as you can expect. Hot, tumbleweeds everywhere, Sand as far as the eye can see in any direction, etc. It's all single home housing so it could be denser, but that's pretty much the only benefit of living there; I grew up with a half acre yard (full of sand and an awkward tree in the middle, but actual land) and it gave my grandparents some piece of mind when we went out to play.
The total land area is also irrelevant: Spain has a pretty low total population density, but that's because most of it is empty. The people live close to each other anyway. You can have a house 20 minutes by car anyway, and thus live 20 minutes away from the hospital instead of 3 minutes if you really like yards that much, but barely anyone does, because the car life is expensive and a hassle