The 4 person example has a lot more usable space though, since you're sharing common space. You're not adding 3 more kitchens. Or 3 more laundry areas. Or 3 more bathrooms (maybe 1). Or 3 more living rooms.

The 270 ft² space might have 100 ft² usable area, but the 1076 ft² could have 700 ft² usable.