You hit on something I puzzle over quite a bit...and I don't mean to de-rail the flow
If i give ten dollars out of the wrong motive, or for egoic reasons, will that money harm the person it is given to? Is the energy of the money somehow tainted?And there is nothing wrong in walking past a person in suffering either. You are not obligated to do anything in this life. If you help others because of a mental image of an enlightened person than your acts are not geniune and dont flow out of a truly enlightened self. Trying to become enlightened through outer action is exactly what jesus warned about when he said that people were "trying to enter the kingdom of heaven violently" and calling people "decorated caskets" because they were only concerned about the outside rather than the inside.
Vernon Howard always warned against charity that flows from a false sense of responsibility and false guilt.
Because if not, it seems that if you give money for the "wrong" reasons, knowing that you have the wrong motive, but are willing to accept the suffering the giving causes in terms of ego identification, then the giving would become altruistic/beneficial at least in the sense that you are willing to take full personal responsibility for the act.
I just give a certain percentage of my income and don't think about it. Then if I see extra need and it seems "right" I give spontaneously, and these are usually small acts of giving....I am waiting for the day I am moved to be generous until it hurts and see what happens...