Topic: Wii control sticks turning green?

Lately I've found the thumb pads on my control sticks on both the nunchuck and the classic controller are turning slightly greenish (or, at least, darker than the white it's supposed to be) Is this a common problem? If it is, does anyone know how to fix it? I tried using rubbing alcohol, to no avail. I don't know why it's doing this. I'm a very clean person, and my hands don't sweat a lot, so...what the heck, Nintendo?

skin sometimes rubs off into the rubber of the joystick. It isnt that you are dirty, far from it, you just sluff skin! (it is normal)

I had that with ink from a comforter i have a blue headed nunchuck joystick & Classic Controller one too xD!

Yeah I bought a new nunchuck the other day and hadn't noticed how yellow my old one had gone until they were side by side.It's just what happens .

Me, I just sweat alot. (I have Gamer's Hand. HA!) But I can usually get that off. Mine aren't discoloring yet unless I haven't noticed.