The problem with this line of reasoning is that there is really no reason why "self" must refer to an individual. Who you are realistically intersects with many

The problem with this line of reasoning is that there is really no reason why "self" must refer to an individual. Who you are realistically intersects with many things on many scales - life, culture, family, individual. They are all your "self" in some sense, and service at any scale will be selfish in such a sense.