How does this relate to the thousands of podcasts that are listed in the iTunes podcast directory and that are freely playable on any podcast app on any platfor

How does this relate to the thousands of podcasts that are listed in the iTunes podcast directory and that are freely playable on any podcast app on any platform? Is this for a special set of podcasts that are using Apple's system to manage access to paid subscriptions? If that is the case, then this seems reasonable.