Revealing mistake: After the crowd boos at Homer after kicking the bomb, Bart is shown walking past The Android's Dungeon and the shot pans over to show Comic Book Guy. Just as the shot begins to pan over, it can be seen that Comic Book Guy randomly pops up on screen.
Revealing mistake: After Homer knocks out the guard guarding the dome, Homer runs into the supplies shack. As he walks through the doorway, his right arm passes through it.
Revealing mistake: When Moe is emptying the beer bottles into the lake, his face is seen turning around without any animation. (00:19:20)
Revealing mistake: When Grandpa is being rolled out of the church, everyone is looking at him. As this happens, look closely at the Squeaky Voiced Teen sitting next to Hans Moleman on the right hand side of the church. As he turns his head around you'll see his eyes disappear as he stops turning his head. (00:06:05)
Answer: The family doesn't treat him very well, particularly Homer. He may have wanted some revenge on them. Grampa is also a little senile.
Phaneron ★