It's probably got to do with the bizarre design that hides the actual link to a productms website as a small element on the page and makes the most prominent links and buttons go to other things instead.
They're not very good at identifying what's actually an "alternative". By way of example, some of their top alternatives to OwnCloud include Dropbox, MEGA, and Google Drive. (All of which completely miss the point - OwnCloud isn't just a file storage service, and one of its key features is that it's self-hosted.)
