You are TOTALLY correct and have just stated the essence of my view of where the seflishness comes from. Your are also correct to point out my overgeneralization; people who write software are IMO the hope of the world. But it is no coincidence that most people who write software have liberal arts educations. The purity of their hearts isn't entirely to their credit, however, since their career choice insulates them from getting their hands dirty and confronting the moral choices that those in other occupations must deal with.
I am an economist and a C++ software developer. When I was young, writing software wasn't about the money. I came to Silicon Valley and was dismayed to find that, here at least, it had become all about the money.