"Clearly the fictional characters are more important, we've just spent a whole book/game/series getting to know them! They're my friends now! This other person? They're just a name online. Why should I care about them?"

Exaggerated for emphasis, but emotional investment is a helluva drug. Having a reality check now and again to pump the mental "This is stupid" brakes once in a while if necessary never hurts.

What do you expect? The Greater Internet Fuckwad Theorem has been holding up well since it was first formulated around the turn of the millennium.