It's the users fault! App.net was a alternative to twitter, but a paid one. Failed. So users are in no position that they are the product sold to advertisers. They actively decided to be the product.
I was really excited about the idea of App.net being a developer-friendly replacement for Twitter, but when I finally got to try it, I was appalled by its complex and awful UI. One thing Twitter does relatively well is be simple. You can write tweets and you can read them. App.net had poor focus and failed to do a simple thing by trying to do a complex thing instead.