Part of the reason for the general acquiescence to tip creep may be that Square is mostly a feature at high-end hipster shops — places that peddle what some might call "treats" and others might deride as "inessentials."

American consumers are feeling a bit of tip creep.

Leaving 15 percent for full service (the former standard tip at a sit-down restaurant), and less for quick transactions, is considered chintzy by some people. “We recommend 20 percent absolutely,” said Peter Post, managing director of the Emily Post Institute, which offers guidelines in etiquette.

Consumer experts agree the average New Yorker is being besieged by an ever-growing number of service workers who are after an ever-growing slice of their spending money. Not only are there more hands reaching into your pocket, they’re expecting more: "Suggested" gratuities can run to 25 or even 30 percent, a number that might have been laughed off just a few years ago.

All this inflation is creating an epidemic of what author Steve Dublanica calls "tip creep."

A decent tip for a waitron used to be 10% then it was 15%, now it's edging up to 18%. (And I could start a whole rant about "automatic" tips.) The service hasn't changed. Why…are we experiencing "tip creep"?