* The story Foster tells to the family after he crashes their barbecue, that ends with him and his family "all sleeping together in the dark", [[spoiler: which seems to imply that Foster intends to [[PaterFamilicide kill his wife, his daughter, and himself]] once he gets to them.]] The dreamy way he tells the story just makes it worse, as he genuinely seems to feel ''that is the right thing to do''.
* The whole movie becomes this once you get to the end, in part due to ParanoiaFuel. Given that many people find Foster [[JerkassWoobie sympathetic]], it makes one wonder just how easily this could actually happen to them or someone they know.
** Really just [[FromNobodyToNightmare Foster himself]]. Basically, he's a guy who had a really [[SanitySlippage bad day]]. An [[RidiculouslyAverageGuy average joe]], the white collar working man, a simple human being who feels [[CorneredRattleSnake pushed into a corner]] [[RageBreakingPoint and is]] [[DisproportionateRetribution lashing out in various]], brutal, over the top ways as possible. And, do you want to know [[FromBadToWorse the real scary part]]? ... [[TruthInTelevision There are people]] [[ParanoiaFuel just like him]].
* The Whammy Burger scene can be this for some, considering that this could happen to ''[[ParanoiaFuel anyone]]''.
* The Neo-Nazi freak whose favorite possessions are an anti-tank weapon and a used can of Zyklon-B.