Tweeeeeet! Fifteen yard penalty for observer's bias. We can see planets with orbits closer to their star much more easily, therefore we see more of them. It's like saying there are far more white cats out at night because you can't see the black ones.
Yes, this is the obvious alternative theory, and much more likely.
Observers bias cant be excluded until we have much better instruments, that can detect Jupiter type planets, or Earth type planets for that matter, across interstellar distances.