I've never understood the argument of, "Well, hey, it's just fan fiction. Of course it'll suck!" I can't imagine enjoying fan fic if I felt that way about it. That isn't to say I always have high expectations, but that argument just feels like it has a general bias against fic and fandom in general, and it seems kind of rude to the writers in fandom who really do love writing and make an effort.

Also, I think there's some difference between expectations and standards. You can have realistic expectations (because let's face it: really good things stand out in part because they aren't dime a dozen), while still having personal standards about what is and isn't enjoyable for you to read.