I think that as soon as an attacker tempts the user with: "follow these steps to access American/UK (substitute a locale that has content your account shouldn't have access to) only films that Netflix don't want you to know!" that the apparent gain for the user will lead them to ignore any warnings. In fact, warning might actually encourage these kinds of attacks since the user could think "that's just Netflix trying to hide something, I'm gonna following [the attackers] guide"