Why free?
Because flipbooks are a basic publishing primitive. Charging educators to use them feels like charging students to use a library card. Every template is open-source, every tutorial is creative-commons, and the indexing script that powers the gallery is itself a few hundred lines of PHP you can fork.
Will this ever change?
No paywalls on existing pages, ever. If we add new services — managed hosting, premium audits, training workshops — those may carry a price tag, but the reference library will stay free.