Do we have to bow/curtsey to all people with an important title?

Even we, as British citizens, ARE NOT obliged to bow or curtsy. In 2011 a polite greeting is enough! It has changed a lot over the last 20-30 years. We are no longer "British Subject; Citizen of the UK and Colonies", but BRITISH CITIZEN now, in our neat, little, European format, burgundy passports!!! (?)