Jessica's Father: Oh my God. He shit everywhere. There's shit everywhere! Damn it! There's shit on the windows! Oh my God! My house is full of shit! He shit everywhere! Look what he did, he shit all over the wall!
Store Clerk: Enough! You're it! And no touch backs, no do overs, no erasies, and this whole store is home free!
Harry: Lloyd, can he do that?
Lloyd: Oh yeah Harry. He can. He did. And now...it's on like Donkey Kong. Pay the man.
Harry: Pay the man.
Answer: Because Harry and Lloyd had poured gasoline all over the car as well as let the pump keep running when they left. So when the hot ash of the store clerk's cigarette hit the gas fumes, it caused the explosion.
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