Hmm... I've never felt guilty about having several ereaders, mostly with the same specs. Sounds very strange to me. I have several laptops as well, but only one TV and no car.
I also never feel I have to justify my wishes to anyone, even to myself. That's something I've often read about people doing and it also feels very strange to me.
Of course I'm basically a lone wolf and avoid any team playing like a plague. Possibly that's the reason. I'm not in the habit of explaining to others why I want what I want.