The reason? Well, I had made new characters, but I didn't want to go on their profiles because I would have to be offline (my other characters don't have friend codes) and so I wanted to decorate their houses while people were at my town. Then I needed to drop stuff, which I couldn't..That's the reason.
Oh, and to do those fun things that people with the code do, like moving furniture and others can see it in other buildings.