Oh and yo can rub through the anodized surface, it's only a few molecules thick. Not with a tissue, but with continuous rubbing. Like a case pressure point constantly rubbing on the anodized surface. Want to do it faster take Brillo pad and rub on same spot and see what happens.
Oh , and stop calling it paint, it's not. The only phone that gets a coating is the silver, that's the raw aluminum color covered by a clear coat, that also will rub off with repeated rubbing. Come on people you have the phone, am sure you are connected to Internet, look up anodizing and read what it is.
The 7000 series aluminum anodized slightly more deeply than the 6000 series. So the 6s anodization will take more rubbing to wear through to the base aluminum.