Pissed

What mechanical processes occur in someone's mind to make them think they can search through someone else's personal effects, take out their two favourite DVDs (let's say "Ali G" just for argument's sake), keep them, watch them and then scratch them beyond all use? At what point does your mind click and you think, "yeah, it's okay to disrespect someone else's property. I feel fine ruining these DVDs, even though I make far more money than the owner, and should really just replace the things." Somewhere, Borat is crying.