Tatooine is not a safe place. Leia's a princess from one of the most peaceful planets in the galaxy.
Not to mention that Tatooine is basically the last place Kenobi would think to hide. He's visited hundreds of worlds, met thousands of people. I don't think he'd even set foot on Tatooine once in his entire life. Didn't he stay on the ship?
If you're looking for him there, you're scrapping the bottom of the barrel.
