So much for not gapping NGK plugs out of the package

They probably pulled the head to do it. They can say that it's the only way to do it, because then that way they can be sure that no metal shavings fall into the cylinder when they are re-tapping it... I just put grease on the tap and it got all the shavings (I think... engine ran fine for many miles later until I sold it)

 

More than likely dropped by some parts guy. That plug won't last more than 30k before the porcelain cracks and deteriorates. Take them back and get 6 new ones if they were in a 6 pack. Hopefully butterfingers behind the counter learns their lesson... not likely though.