[ghufran_syed]

I think your example is pretty much the definition of zero-sum thinking - why would a benefit to you automatically "subtract value from the system".

I would argue it's a positive sum transaction - the person you helped receives something of value, from a real human they know, strengthening the relationship between the two of you, others in the community see that and are encouraged to do the same, and the recipient feels a sense of obligation to at "pay it forward" any way they can leading to further "good works".

Have you really never received anything of value from someone who had no obligation to do so? Not even a lead on a new job, or an introduction to someone who helped your career, or a mentor? If so, do you really feel the situation would have been better if that information had arrived in an anonymous form?