A similar example, from a Chris Farley movie:

Tommy: Let's think about this for a sec, Ted, why do they put a guarantee on a box? Hmm, very interesting.

Ted: I'm listening.

Tommy: Here's how I see it. A guy puts a guarantee on the box 'cause he wants you to fell all warm and toasty inside.

Ted: Yeah, makes a man feel good.

Tommy: 'Course it does. Ya think if you leave that box under your pillow at night, the Guarantee Fairy might come by and leave a quarter.

Ted: What's your point?

Tommy: The point is, how do you know the Guarantee Fairy isn't a crazy glue sniffer? "Building model airplanes" says the little fairy, but we're not buying it. Next thing you know, there's money missing off the dresser and your daughter's knocked up, I seen it a hundred times.

Ted: But why do they put a guarantee on the box then?

Tommy: Because they know all they sold ya was a guaranteed piece of shit. That's all it is. Hey, if you want me to take a dump in a box and mark it guaranteed, I will. I got spare time. But for right now, for your sake, for your daughter's sake, ya might wanna think about buying a quality item from me.