Most people will say "no" but that mint can make a surprising difference. In the study, giving diner's a single mint at the end of their meal typically increased tips by around 3%. Interestingly enough if the gift is doubled and two mints are provided. Tips don't double, they quadruple a 14% increase in tips. But according to the study what is even more interesting. If the waiter provides one mint, starts to walk away from the table but pauses turn back and says "For you nice people here's an extra mint" Tips go through the roof. A 23% Increase, influenced not by what was given but how it was given.