"The bottom line is money. Developers always want to squeeze more units"
Any developer for who money isn't the bottom line isn't a developer for long. Per square foot of construction, more units generate more rents. Two studios generate $600 a month, vs. $900 for a 2-bedroom, for the same floor-space. Three and four bedroom apartments are almost non-existent for this reason.
The only way to get a 3-4 bedroom place in the city is either to buy an hold house, or buy a condo. Houses are attractive, because they can always be expanded by 'sweat equity', at some later time.