No, buddy, it's the reverse. The sparsest provinces with rural backgrounds (the Castilles [except for maybe Zamora-Salamanca-Leon] , Aragon, Extremadura)... are the poorest. The most populated ones are the ones with the most quality jobs and people has much better salaries and ofc the cost of everything it's on par: Bilbao, Valencia, Barcelona, Madrid...

Also, as they stated owning a flat in the center of your city or town it's expensive as fuck, while owning a 'villa' in the outskirts in the middle of nowhere in Ye Olde Farmtown it's dirt cheap.