There was a diary on it last week - http://www.dailykos.com/...
The patrons apparently showed NBC New York proof that they left a 18$ tip - http://www.nbcnewyork.com/...
But a family contacted NBC 4 New York claiming their receipt from the restaurant shows they did leave a tip, and provided what they said was a credit card statement as proof.
The husband and wife, who asked to remain anonymous, showed NBC 4 New York a receipt that appeared to be printed at the same minute, on the same date, for the same $93.55 total, except with an $18 tip.
They also provided a document they said was a Visa bill, which appears to indicate their card was charged for the meal plus the tip, for a total of $111.55.