Yet, "free to play" games are ludicrously profitable. Surely a large part of that is addiction, but there also is a tech problem here. If paying for a newspaper article has lots of friction (sign up here, confirm email, credit card, 2 factor confirmation, now you have a subscription instead of just buying; cancelation only by carrier pigeon at midnight), then no way.

That is also why the Google and apple appstores can charge such large fees. Sure, buying on websites and sideloading are possible but much higher friction -> many customers simply won't bother.