I'm 90% certain I recall reading somewhere that those who use the app cannot see the Wall and are not notified of posts on it.
They'd have to work in a different kind of payment system unless it can be accessed through Ink, in which case, aren't we just talking about Premiums vs Freemium's wall they've set up?
I'm not thrilled with that sort of wall either, but considering Patreon's "adjustments" in the past week, I doubt Tapas will be jumping at the bit to "make super awesome extra content lock for Freemiums to use the Ink wall lock just like our Premiums!" ¬¬ Sad to say.