Some people want to help others if they believe that the person they are trying to help will be useful to them in the future...
some people want to help others because they genuinely have passion for helping people and they believe that is their own best way to give back to the society
some people also want to help others in other to get some sexual relationship with the person...
and there are also some people that help others just to use it as a way of seeking validation from the public or use it as a publicity stunt,,this is common among some celebrities especially those that love attention so much...
so the bottomline is that different people have different reasons why they help others....