Ryan, selfishness is very much a part of human nature, though not in any Randian way. Personally, I think it's rooted in our inability to see beyond ourselves in any meaningful way. We can't envision the world from our own viewpoint; it's almost impossible to see it from another's.
Of course, we're trained from childhood to be selfish. We are taught to keep to our own world, and not try to put ourselves in the worlds of strangers. Television teaches us that violence and brawn are good, and that intelligence and knowledge are bad.
It's not just television, of course. It's everything. That's why pop music is rarely good.
Harlan Ellison reported (in "The Glass Teat," I think) that a man broke into an apartment and locked himself and the woman there in the bedroom, where he repeatedly raped her for several hours. Her son started pounding on the door and crying, so the man said, "Go watch TV." The child did.
Yes, he was only a child. But isn't that what we do? When painful things happen, don't we turn our backs on it?
Anyway, that's my take on it.