Developers, too. Until you study and play with git for a long time, local/remote branches and pushing/pulling are hard to understand and very hard visualize. With Gitbox it's like reading your e-mail. I promote it at work as "the git client with five buttons" because that simplicity is worth a lot.
Some of the applications on my computer that are bigger than Gitbox: Google Chrome, Wireshark, Inkscape, iPhoto, Komodo Edit, etc. My hard drive barely noticed when I downloaded Gitbox, so practically the only difference was a few extra seconds of download time that I didn't notice, that's all I was trying to say. Your comment was helpful to the developer in the end, so kudos.