User monetization with group access?

Paid group membership (in turn granting access to specific categories) is an existing feature. Take a look in #plugins

Examples include Patreon, Procourse Memberships and Subscriptia.

If you have an existing website which handles such memberships you can also deliver group membership information via your SSO payload.

Users can’t charge others fees directly on a site they don’t own, would it make sense for them to even be able to?