Sure, building a structure is cheaper than not building a structure, bit to an extent, usually height above 7-8 stories, it gets cheaper per SQ ft to build as y

Sure, building a structure is cheaper than not building a structure, bit to an extent, usually height above 7-8 stories, it gets cheaper per SQ ft to build as you go up. That's before you factor in the cost of land which tends to be one of the most expensive parts of building in a city, that also goes down per unit built. I'm not sure, 'should we build a structure or just pave a field is really a good comparison here'