While some people don’t consider themselves to be citizens of the world, traveling will inevitably expose you to new people, many of whom are less fortunate than you. While I’d never suggest that you give handouts to every beggar and busker that you encounter, you should be a responsible and respectful human being when you are a visitor.
There are plenty of ways to leave a positive impression while you are traveling. Blog about worthwhile causes that you encounter (if you’re a loser with a travel blog), spend some time volunteering during your trip or simply treat people with respect and dignity no matter their station in life.
Whether you give a peso, publicity or just your time, leave a lasting impression with the people that you meet by improving their lives. And sometimes that takes nothing more than a smile.