I have/had that zipper on several bags and it doesnt really bother me. I kind of like the fact that I can stick something into the side of the bag without having to unzipper it.
I have one on my Bleecker Tote, and I don't mind it too much, but ask me again when I start using it for school. I do like that I can stick my umbrella right in without unzipping, like I do with my Ergo Tote.