Every time my computer starts up Google Drive decides to download some 20-30 different files (which I can't find on the file system since its tick icons don't work that great and are still in sync mode when it isn't syncing). This amounts to some 180MB. Why? It wasn't downloading when I shut down the previous night, and there were no document changes to my account.
While I hadn't changed anything, my shared folders had new documents others had added in. These changes don't appear in "Recent" on the Google Drive web app it seems, but I found them on my filesystem with the date.