Everybody hates it, but everybody does it.A recent poll showed that 40% of Americans hate the practice of tipping.(1)________________________________. In the America alone,tipping is now a $16 billion-a-year industry.Consumers acting rationally ought not to pay more than they have to for a given service.Tips should not exist. So why do they?The conventional wisdom is that tips both reward the efforts of good service and reduce uncomfortable feelings of inequality.The better the service, the bigger the tip.But according to new research from Cornell University,tipping no longer serves any useful function.The paper analyzed data from 2,547 groups dining at 20 different restaurants.The correlation between larger tips and better service was very weak.(2)_________________________________________________.In America, the custom has become institutionalized,it is regarded as part of the accepted cost of a service.According to Michael Lynn from Cornell,tipping relieves anxiety about being served by strangers.And, says Mr. Lynn,“in America, where people are outgoing and expressive,tipping is about social approval.If you tip badly, people think less of you.Tipping well is a chance to show off. ”While such explanations may be crude,the hard truth seems to be that tipping does not work.It does not benefit the customer.(3)______________________________________.Service people should “just be paid a decent wage”which may actually make economic sense.