Server sided? Not everything

I was thinking about player housing and I come to figure out why they are not putting it out yet is due to the heavy population and the toll it would take on our servers, The reason for my Post is because there are some things that are held on the players end that most if not all other mmorpgs do not do. Character skills ect. are saved on our end not the server end which is very odd but it tells me they really have to upgrade the server size before they can even introduce independent player housing.