That doesn't really say much. I have never said that no such thing exists or that running on donations/as a collective can't be done.

But it is rather an exception than a rule, esp. at the scales we are talking about (e.g. Reddit or Twitter), with world-wide audiences with varying legal and financial regimes.

Look at newspapers. Look how many people actually bought subscriptions to popular services like Twitter, Instagram or Facebook - vs how many are using them for free.