It is always good to show courtesy to fellow human beings, we find this is often lacking and when you starting showing courtesy, some mistake it for meekness or consider us to be a pushover.
One other issues is that fact that, many service sectors lack 'Professional Courtesy' in our country. People get paid to do their jobs, when it comes to discharging their duties towards their fellow clients in need, the same employees behave indifferently. I find this disturbing in some healthcare and some public sectors. For instance it is professional courtesy for a doctor or a lawyer to discharge duties without a fee or with a discounted fee, when the client is a fellow doctor or from the same profession. Once we bring in the culture of having professional courtesy, then we can imbibe the same in our social and public life too.
It is not that only the educated or the elite class can show courtesy, anyone can show courtesy and it enhances our image and the interactive atmosphere a lot.