Woah, thanks a lot. This almost feels like synchronicity, I just spent the weekend looking for scans of this. I made a bunch of icons with what I managed to find, with this I'll probably make a bunch more, it makes me ridiculously happy.
I don't think it's Clamp in particular so much as it is all popular things, whether they be music, movies or print. In the case of music and movies I think it defers a majority of people from future purchases, but in the case of print, it's a smaller amount.