I really support the idea of a couple reasons.
The obvious - it's fun to have your own little niche of space. I played Lotro for a bit, but I got bored (it was all kill x amount of monster y and I'll give you z) but I really enjoyed the housing and that you could to an extent decorate it to your liking.
Currency Sink - they had 'rent' you had to pay. I forget if it was weekly or monthly, this was in 2011 I played, but I remember it being fairly expensive and getting currency out of the game. I am not bragging when I say I have 15 plat capped mules and a plat capped platinum bank. I didn't do anything special to get it, just plat and selling to venders/deconning over years, I didn't sell awesome items, it just builds up because there is not much to spend it on. Repairs and consumables are negligable costs compared to the average players daily intake, and with most of the loot being btc and bta there really isn't that much of a secondary market to put the gold sinks in the auction to counter much of daily generated treasure value of the players just going about thier business. The cosmetic reaper items are nicely expensive and required every life, but with all things not everyone uses them and more things that are natural to spend plat on in the game can only bring value back to plat. Guild ship and amenity costs were helpful for a limited time, but once acquired that falls off too.
Oppurtunity to put in a place open to all the toons on an account to store cosmetics. Make this wardrove everyone is talking about.
With everything being btc/bta that's worth having, storage space is an issue. It's not like we can sell an item we're not going to use for a while (sinking plat) and then buy it again from someone else later. So having a special 'bank' for just cosmetic items would help players with the inventory issues, and incentivize people like me that enjoy playing around with my toons look to actually buy more off the ddo store becuase I'd have a place to put them.
Just a turtle rant on why I think it'd be a good idea.