Because I could ask all those who are attacking the prequels repeatedly and strongly exactly the same.
It just gets old very quickly and feels a bit too much like jumping the internet bandwagon to me. I know, it's no fun to attack the millions of films out there that are way worse but also way less well known, but it still bugs me.
YOU found them average. I found them great and I am a huge fan. I defend what I like, it's that easy. If you wanna call that psychotic, be my guest. *shrugs*

That being said, I can certainly laugh about the films or parodies. I love the Robot Chicken episodes, for example. If someone only tries to mock the films, they easily lose me, though.