It’s a practice called double-dipping, and as George Costanza was famously scolded for in an episode of “Seinfeld,” it’s on par with “putting your whole mouth in the dip!” Now ...

A 1993 episode of American sitcom Seinfeld highlighted the potential hazard of double-dipping when George was given a lesson by Timmy on the social etiquette of eating crisps with dip.