This is something I have noticed as well. If I try to watch Netflix on the Roku, it wants me to pick a primary network, but I haven't done that yet and others in the family who live out of state can still watch it on their smartphones or laptops. Once they force a primary network to picked across all devices, then we will drop Netflix. They have been very, very clever in media relations to publicize all the new sign-ups, but they haven't dropped the other shoe yet that might cause cancellations.
They are trying to publicize the sign-ups to get people to give up and get their own Netflix accounts and by the way, the cheapest ad-free version of Basic just got dropped, right before results were being announced this week.