Now let's imagine they do prevent the game from running without any update with, let's say, FW 11.2. For most people, it wouldn't be a "problem", since they are connected to the Internet and configured theit NNID account. But now, let's imagine that in some months, when new 3DSes come with this FW installed, a random guy bought one + a copy of AS. The guy doesn't have an Internet connection. When he tries to use the game, the console won't let him. And not only many people will be angry about this, but Nintendo also broke its own TOS, since it would force the guy to accept the NNID TOS and not only the console's TOS.
I'm not sure I was really clear, but you probably get what I'm trying to say