Why are they the way they are? Economic reasons? Blind adherence to traditional ideas? A reflection of our values?
The rooms are isolated from one another and subdivide a bigger space. Walls give the illusion of privacy and trick us into believing we are alone. If we are in a room by ourselves, we are alone, but if we knock down the walls, then we are exposed and among company. People say they need "my space". A space to call their own. A space which when outsiders are inside, they realize their wishes are secondary. A house within a house.
The most well-off among us tend to have individual bedrooms for each inhabitant, except the male-female heads of household that bed together. Each child has a room and then a separate room for particular activities: an office for working; a dining room; a sun room; a laundry room. We arrange our rooms with regard to our priorities, conscious or not. Our living rooms are arranged around the TV, giving everyone as good a view as possible. The television is the glowing star of the room and we all give it our complete and undivided attention. This is no place for small talk, unless it's during commercials. Our dining rooms hold a big platform that presents us with our feast and we circle around like a pack of animals. A meal prepared with such care and made to look so appealing, it warrants a prayer in thanks. The office has a large desk with a computer atop. We surround ourselves with books, reminding us of the work we've done in the past and can do again. A desktop lamp is present in preparation of working until the wee hours of the evening. A paper shredder for our mistakes. The kitchen is large enough for two people to cook, but rarely used as such. There are pots and pans of every size. Only 4 people live in the house, but there's 15 plates each of 2 different sizes. 10 bowls. 25 forks, spoons, and intentionally dull knives. A block of steak knives that have a couple butcher knives, a pair of large scissors, and something I cannot identify. This is only half of the kitchenware since the good China isn't used. There's usually a basement that has a storage area. A place to put a bunch of stuff you'd rather not throw away but can't find a place for: trophies, photo albums, old clothes, outdated electronics. Proof you lived in an earlier time with something tangible to show for it. Then there's the stuff that you'd sell if you had the chance, but no body wants it. But it's worth something, you can't just toss it out.
Your old stuff cannot be among your new stuff, however. This would be cluttered and tacky. In order to not be obligated to apologize to guests before they enter, we must have vacuumed, dusted, wiped up, scrubbed down, washed, dried, polished, plunged, disinfected, and deodorized. Things must be put away. Trash goes in the trash can. Dirty clothes go into the dirty clothes hamper. Plates go into the plate cabinet and silver wear into the silver wear drawer. The magazines in the magazine rack and the coffee table book on the coffee table. Everything has its place and it's up to us to put it there. Complete control and knowledge of our surroundings. We are the Gods of our homes and impart our own divine plan of which only the inhabitants know the code. It is our decision where the forks belong. This is what makes it our home. It is our material possessions that hold proof that we were successful in our lives. These possessions are validation of our memories. They assure us that our interpretations of the past are correct, no matter how distorted they become. The memories that are attached to our belongings whither and decay with them, as do we. Inanimate objects are alive in this way; in their ability to die and lose all meaning and value. Therefore we cherish them and store them and build rooms for them and organize them. We define them and in turn they define us.