This behavior is not different in quality, though, just in quantity. I think that when you call yourself a "fan" and spend your time "wondering about the intersection between PG's fans and Stephenson's fans", you are expressing the same kind of devotion shown by the author.

So yes, there is a gap between you and the author. But it is a relative one. And I happen to think it is funny to see people judging someone else's behavior even when they show the same behavior. It's no different than pill-happy moms worried about their kids using drugs, claiming there is a huge difference between prescription drugs and whatever-kids-take-these-days.