Art can be done for arts sake. There are plenty of people who paint, write poetry, etc. for themselves who have no intention of trying to sell it. The fact that some of these people do not live alone and thus family members can see the artwork doesn't change the fact that the artists doesn't plan on the public seeing it/reading it. However, the meaning behind the term Art for Art's Sake isn't that you do or don't want people to see your paintings etc. It means that you create art with no deeper meaning than to create. In other words, you are not trying to teach people anything, change their viewpoints on issues, comment on social issues etc. You create because you feel the need to create. What other people get out of your art, if anything, is up to them, not you. Other artists do indeed create art with a specific purpose in mind.