The "ask me" face

When I was a child it was already the same phenomenon: You can have a crowd of people waiting for the bus, but people ask me for the time, when the bus is going to arrive, the way or are even telling me the stories of their lives. I can wear headphones and listen to music or look on the ground, people will tap me on the should and ask for something even if there are plenty of people around they could ask instead. I often wonder if people feel that I like to help other people and see it in my face. Personally I think it's a strength to help others, but in the interviews I have ( I'm currently looking for a new job), the interviewer is often worried if I will be able to say "no" and to be tough enough when negotiating. I must say I'm a little bit fed up that you have to be egoistic and selfish to get what you want in business life. I can say "no" but I do it in a more comfortable way for both sides without being choleric and affronting someone. I have made the experience that if you treat people in a positive way and help them, they will also be willing to help you in a bad situation. And so far I have managed to get along quite well with this attitude and I don't want to change myself just because some people think that it's a weakness and I won't.