The building has indeed been built for 2 reasons, but not the 2 reasons you suggest. It’s simply :-
2) Planning corruption
Greed as the developer has tried to maximise his profits by building 150+ apartments on a plot size that would only take 4 or 5 villas
Corruption as the town planners have clearly accepted bribes to approve the construction. This building (and there is now another, but a few floors less) is so out of character to the entire area.
I don’t know if you know the area, but there are 1000’s of square metres of waste land around and in El Ejido. It’s is certainly not farmland.
With regard to the millions of acres of plastic greenhouses in the area. This is slowly but surely moving to North Africa, it’s now a lot cheaper to grow the vegetables there. Spain is no longer a cheap country. The reason for the growth of El Ejido over the last 20 years has been production of fruit and vegetables, but unless another industry comes to the region, I don’t see future growth continuing.
Actually I see the developer of this project going bust, as the resort of Almerimar about 4 km away now has an abudance of apartments for sale. There has always been a 20~30% premium for a similar apartment in Almerimar, but this recession is making Almerimar affordable for young couples. And in fact a young couple, from El Ejido did just that; bought my apartment in Almerimar.
Unless you want high rise living there are 1000’s of better choices in the area.