Tourism
The price for a ticket into space, and eventually into orbit, is going to drop drastically, and once there's a destination up there--a space station--the appeal will grow. At this point, people will start figuring out ways to make money up there in other ways.
Also remember, the goal is not to get tourists up there, the goal is to have an initial market for cheaper launch vehicles. You'd be amazed at the number of things that become financially feasible in space when the transport costs come down.
SpaceX is not primarily going after the tourist market. They're trying to underprice the regular launch market.