Well, I like having everything on one partition. I also like being able to change OS's at startup. Then again, I never really boot into OS 9 anymore, so it doesn't help me much...
Oh, and normal is relative. I only have one partition on my main drive with OS 9, OS X, and the rest of the world on it. I like not having to care which disk I'm saving to, and which disk my programs are on, and so forth.