I also agree that it is about the actions more than what you gain by doing so.
Charity is a good example of how altruism helps yourself, I donate to charity every now and then and of course it makes me feel good about donating, thus the act has an emotional gain for me.
But I don't consider it "altruistic". I help them because I want to help them and enjoy having done so, and not out of some innate sense of ethics or of what needs to be done.
I think people doing altruistic things do enjoy them, but they don't do them because they enjoy them. They do them because they need to be done, and the enjoyment is a side effect.
Of course, this distinction makes it incredibly difficult to know if someone is actually being altruistic or not.
For example, a restaurant owner might serve food for free for homeless people for increasing their own reputation and social wellbeing, vs the owner who does it entirely out of the goodness of their hearts. The net result is the same, so why worry so much about the motivation behind it? I'd say they're both equally good people, in this example.
Being able to be generous and therefore altruistic is also a decent signal to the rest of your group you're fit and healthy.
What is the difference between the two conditions? The only one I can think of is that removing the side effect does not change the behavior, but removing the main motivator does. How is this significant though? Is it easier to lose enjoyment from altruistic activities than to lose a sense of responsibility? Is pleasure more fickle than duty?
That distinction, IMHO, also makes the definition of altruism so narrow as to be useless.