Honestly, I find this position bewildering. Why give a damn? Because you are, and you exist in the world, and you know joy and suffering. And if you do, then odds are, so do the people around you. There may not be logic compelling you to be kind to them, to attempt to ease their pain...but there is kindness. Which, I suppose, is the basis of my morality in the end. Which makes it not so much morality as compassion? Maybe. The impetus is compassion; the overall structure for best implementing compassion is what I would normally call ethics. And the pagan creed, "do as ye will, an' it hurt none", comes pretty darn close to being a decent general guideline, though I guess I add in something like, "if you can afford to, help." Where the exact value of 'afford to' is left up to the individual, their own needs, and their own ethics.
I also feel like Columbine missed a big part of religion/faith -- praise. Praise for the glory of the universe. And maybe some thanks. I'm not religious, and I don't actually possess any faith in a Higher Power. But I won't rule out the idea that there might be Someone out there looking in -- and if there is, I don't need Them for my morality, but I wouldn't mind a chance to say "thank you" someday. "Thank you, and nice job. Great ride. Can I go again, please?"
"Or, if you need a hand in the kitchen..."