When you ask the cashier for the total before they ring up the last item, so they will forget to scan it. Only works if you are purchasing 4 or more items, the cashier is not putting the items into a bag one at a time as they scan them (or you are skipping bagging altogether), and the last item doesn't have a beeper. Even then, it doesn't always work, but when it does, it feels oh so sweet, especially if the item they forget to scan is the most expensive one. The term is a play on the word shoplifting, combined with the name of the inventor, who is occasionally known as Schnappoulop.
Guy 1: Hey man, I just went to a liquor store up in Canada where the cashier was really stupid. I asked her what the total was after she scanned the first three bottles, and she forgot to scan the fourth bottle.

Guy 2: So you got it for free?

Guy 1: Yeah, it' called shnoplifting!

Guy 2: Dude, I cannot believe you shnoplifted and sneaking alcohol across the border!
by schnappoulop September 25, 2012
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