Tips are not bribes. In the US, nobody is going to deny you their service if you don't tip (well they might spit on your burger the next time!) In the US, bribing is done on a larger scale and in a more guilt-reducing polished manner. So polished that many people (like you obviously) don't even consider them as bribes. Example of bribes in the US: 1) When a police association calls you for a donation in exchange for a decal that you stick on your car. 2) When drugs companies take doctors on expensive junkets as a reward for prescribing their drugs. Did you know that drug companies keep track of all the drugs that is prescribed by a doctor. 3) When lobbyists finance political campaigns. These are all perfectly legal bribes.