Honestly, it has nothing to do with roleplaying.
I disagree. But that goes far into the territory of Role Playing Theory right now ...
I'm currently playing SIMs Medieval. Looks and plays like an role-playing game - made from a completely different perspective than most role-players (especially "hardcore role players") used to see.
And yes, you can decorate rooms there. You even own a house. You have to sleep and eat there. And you get experience points.
One of my favorite parts of Divine Divinity was when I marched into a town and had some kid say to me "I want to be a murderer like you when I grow up." That was right before I killed him BTW.
I wouldn't want to play with people who are able to do this.
I just can't stand this kind of insensitiveness.