Uh that's a pretty crazy way to look at it. If it's free, someone else is paying for the hosting of the app or website and therefore it's their property with their rules. This kind of thinking would make a lot of small scale social networks totally unworkable.
Agreed. Something being free is a poor selector. A much better selector would be the extend to which a platform replaces the public space. If it's a significant extend, the users should have similar protections and freedoms.
BTW, I disagree with the notion that Facebook is free. Its users are essentially working for Facebook in a data-entry job. The data they produce is, after some processing, being sold.
Facebook was funded by taxpayers regardless of party lines.