Med-
I think that the reason you aren't getting it is that you only understand libertarian thought in theory, not in practice.
I'm 42 years old. I quit high school when I was 16, and I make 30,000 a year. I donate regularly to a charity, as well as side projects when I am able (just this last month I donated 500 dollars to a fellow employee who needed a new prosthetic leg.) I am NOT a self centered or greedy person; but I feel very strongly about defending YOUR right to be self centered and greedy.
Your question about how I became a libertarian really made me think- I really hadn't contemplated my personal political arc, and how I went from a socialist to a libertarian in 20 years. I really do think a lot of it has to do with a natural maturing process that just comes from "living life"; I came to realize that people are by and large responsible for their life situations, and that you cannot save them from themselves. I also realized that I was happiest when not dealing with government in any way shape or form. In 42 years, I have not been served efficiently by any government agency I have ever come into direct contact with. Even outside of government, my experiences with groups of people working together (beauracracies) have been largely unpleasant. I also have gotten in touch with the fact that I like to choose my own values, and I don't want to be coerced by others into activities and projects that they think are important. However, I have found that people as individuals are basically good. Its when they get into groups that things start to go off the rails. Somehow, groups of people are able to spread the concept of responsibility so thin that it evaporates. But individually, people tend to be very responsive and responsible. These experiences have led me to the conclusion that individual responsibility is where the answer is.
I think we view the world very differently. When you talk about a corporation being evil, I can't relate. If you wanted to talk about the individual customer of the corporation being evil, then we might have something to talk about; the individuals who spend money there are the ones responsible for its success. If you talk about an employer being unfair, I can't relate; an employee can go find work elsewhere. The employer/employee relationship is not adversarial, it's cooperative. If anything, the employee has more of the power in that relationship. I sincerely believe that (with rare exception) people responsible for their own situations. If I saw a grossly disfunctional system, I might feel differently. But I don't. We have some problems, sure- the biggest one being what we do with our drug addicted and mentally ill (we call them "homeless.") But even our poorest citizens can only be called "poor" in relation to the megarich. Things are okay dude, really.
Lastly, I'm not a pure libertarian. I happen to think that the health care system needs some fixing, and it's going to take government intervention to do that. I'm also a little uncomfortable with some libertarian thinking when it comes to the environment. But I call myself a libertarian because it is the system I MOST identify with. You might be getting a little hung up on the label.
Now all of those opinions can change over time. I expect some of them will. But right now, they make sense to me. And I'm not a greedy rich person, I'm a lower middle class dude, and a really nice guy. Just ask me.