I missed the part where you limited the free reads to people who can't afford $5 a month. If you check their tax returns, you can send friend links to those who qualify. Otherwise, you are just letting freeloaders freeload.

The Medium author's pool works because Members Only articles are for, wait for it, MEMBERS ONLY. If you give the article away, it ISN'T for members only, so why should you be paid from that pool?

Giving away Members Only articles creates a tragedy of the commons. If everyone did as you do, why would anyone join? Then how would you (we) get paid? You are shooting yourself in the foot, only your are too busy being a smart-ass to realize it.

That's my reasoning.