Not that I disagree with your overall assertion, but without economic incentive there is really no incentive in most cases. For someone who does have economic incentive, it's really business risk reduction 101 to not pin your application to a network of invisible and hidden dependencies that you have no control over.
Right, using f-droid and installing open source apps where the only incentive is the user's benefits.. that's a breeze of fresh air. Of course it can never give you access to instragram or any particular commercial platform like that, but you can handle your own data with dignity.
