This is not a selfless action at all - it is done with the expectation of benefiting yourself. It is a rational bargaining tool; I fail to see the concept of 'right or wrong' come in to play at all.
The 'rational bargaining tool/reciprocal altruism' is one aspect, kin selection is another, along with reciprocity, and Eusociality. I don't know why you only focused on reciprocal altruism?
So you understand that the inclination towards kind actions are explained by evolution, but you believe because it isn't completely 'selfless' it isn't moral. I think the problem is your definition of morality.
What is your definition of morality?
I've never known anyone help another human being and not feel good about it on some level, but I don't consider that immoral - nothing wrong with feeling good for helping someone.
The only people I've come across who believe that if you help another human being and derive any personal benefit from it, then you're immoral or 'not truly moral' are religious folk.
Maybe you're viewing morality from a religious perspective still? (ie. you shouldn't derive any personal satifisfaction or gain from helping other human beings)
I don't see how this relates to morality. Having sex pleasures urges that we have, but it isn't relevant to any moral compass we may or may not have.
I wrote that to help you understand that the notion of 'survival of the fittest' isn't referring to individual survival - which you believed judging by your response. It is referring to traits
within a species that ensure the survival of that species. Like the inclination to help other members of your species.