"The very practice of dangling a toy or other premium to get kids to pester their parents to go into the restaurant and buy food,junky or nutritious, is unethical and,we believe,illegal."
VOA: standard.2010.06.24
Those who make it a practice to leave extra large tips to a restaurant server may be naturally generous, or perhaps just thought the service was excellent.
Even more immediately, if the restaurant shares service charges among all employees, a common practice strengthened by this ruling, all of the servers would be cut out of a piece of the pie because of this sort of behavior.