We only have reason to have such feelings for people in our "tribe" though, people whom helping actually does help ourselves and/or our genes. Heck, you could make a perfectly sound argument that a desire to help people without a direct link to us through our tribe (members of our society and/or subsection of such) is a faulty response, the result of a hunter-gatherer brain in an environment that too rapidly became ill-suited for it.
Actually, reciprocal altruism is a distinct idea from kin selection, though they do share many similarities. The main difference is the way in which it ensures an advantage for your genes.
In kin selection, whether you help yourself or your brother, whoever survives will pass on your genes. Hence there is no real cost for the gene if it is one or the other who survives, so long as at least one does.
Reciprocal altruism has you help another in the expectation that they will help you back at some stage in the future. It's effectively a gamble that a small cost when you're better off can lead to a reward when you're worse off (and need it). One common example brought up* in this regards is vampire bats, who need to feed nightly to avoid starvation; a bat that's sucessfully fed will often regurgitate blood to one that has not, under the expectation that the same will happen if the roles are reversed.
*There is some debate as to whether this is pure RA however.