Parodied: Two families feud across several generations because of this trope, but have forgotten why it even began.
The hero is hunting the villain to revenge somebody who's only vaguely related to him. "You killed my father's cousin's mother's sister's daughter's son's third wife's roommate!"
The hero hunts the person who killed his goldfish.
The slight is even more comically petty: "You stole my sandwiches!"
The hero devotes his entire life to track the villain only to discover he died years ago of an unrelated cause. Realizing he has wasted his life for nothing, the hero suffers a mental breakdown and kills himself.
Reconstructed: The hero gives up his quest for vengeance, and comes to peace with his loss, only to discover that the villain is a right bastard and really needs to be stopped regardless of his petty concerns. Thus, his want for vengeance is replaced by a want for justice.
Zig Zagged: "You killed my father!" "No, I am your father!" "What, seriously?" "Yes. You see — *UGGH*!" "What, where'd that knife come from?!" "Me, and he's not your real father!" "How would you know?" "Because I KILLED YOUR FATHER!" "Meh, I never liked the old bastard anyway."
The Hero wants to kill the villan to avenge his father. Another person beats him to it though and kills the villan. It is later discovered that the man who killed the villan is the hero's long lost brother and he killed the villan to avenge their father.
Averted: The hero's father is alive, or died of causes unrelated to the villain.