lol, very strange. any way, im sure you could sand them off, but i dont think it would work with a macbook pro keys as they are translucent underneath, for the backlight to shine through. you cound maybe cover up the underside or something, or paint over the top. either way, itll be a bit of a bodge job.
(also, on an added note, the wireless keyboard keys cant be transferred to a mbp, as they use a slightly different mechanism, so you wouldnt even be able to swap with non translucent keys. maybe the white macbook will? who knows.)