Sounds like a nice thing to have. The person who built it was really thinking ahead to provide access to that area. Most people wouldn't have even thought about it. That's the nice thing about a custom built house, you can do neat little things like that.
I don't know if someone else had originally picked it or what. It was just about finished when he found it - he ordered the colors/appliances/carpeting, etc. and then after we got in, he installed a sliding glass door since the wall where he put it was already finished when he found the house.