It has been the American way for more than 100 years. After eating out in a restaurant, diners tack an extra percentage onto the bill—typically 15% or more—for the waiter or waitress who served them the meal.

But the fairness and future of this entrenched U.S. tradition has been debated in recent months, especially after prominent restaurateur Danny Meyer announced plans to end tipping in favor of higher menu prices at his full-service eateries in New York, including landmarks such as Gramercy Tavern.

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