That has also been my observation. However, where the US stands out alone for me in the developed world, is that tipping hasn't just become common in a few isolated situations - like getting something served at the table or getting ones' room cleaned. I can somewhat understand those because you as a customer can judge best how labour intensive / stressful your particular case has been for a low paid worker. But in the US it's everywhere. Why the hell do I have to tip a hairdresser? A taxi driver? A gas station serviceman? They have prices based on workload and materials anyway, so please, why do I have to figure out your correct salary for this interaction based on some arcane percentage system myself? This, at the end, is just what I call unprofessional. If you want to see how professional the service industry can get - as others have pointed out - just visit Japan.