How practical is Ethical Egoism?

Last week in class we discussed two ethical theories focused on serving your own self interest.  The first was psychological egoism which focuses on making ourselves as well of as we can be, including helping others to ultimately do best for ourselves.  This viewpoint is a descriptive notion of the way reality works.  The second theory we discussed is ethical egoism, the theory that our own ultimate moral duty is to improve your own well being and self interest as much as possible.  This theory is prescriptive, meaning that this is how we should live our life.

Having grown up in the church, I have attended many charity fund raisers and 30 hour famines to raise awareness and money for those in need.  World Vision is a company largely focused on spearheading the project of world hunger in developing countries.  After reading about these two ethical theories, it really made me reflect and ask myself why I sat through countless hours of charity - was there really an alternative motive?

(here is a link to world vision http://www.worldvision.org/our-impact/child-protection)

Honestly, back when I was 8 & 9 I genuinely cannot think of any other reason for participating in those events except that my parents required me to be there.  I was not acting out of my own self interest, and I definitely was not acting in a way focused on the individuals we were trying to help.  I was just there.  Going through the motions.  But perhaps my cognitive abilities were not fully developed enough to appreciate and understand what is was I was doing?

Now at the age of 20, I still find myself doing charity work and donating to those in need.  But, after a lot of introspection, I think it can be tied to a good feeling I receive after I knowingly help those in need.  That even though I am donating to help others, I am still satisfying my own needs by donating and getting that good feeling.

Though this theory is an absolute theory, meaning all actions are to be carried out in a self interested way, which I simply do not think is possible.  I do believe that many of our actions are caused by self interest, but that we still can maintain to have exterior motivation for our actions besides personal gain.