This can happen with any wheel cleaner.
True, but I haven't experienced that with the conventional wheel cleaners I've used for years now. Although, if the wheel/rotor was hot, it's certainly possible (my wheels/rotors were cool to the touch). As you know, if used correctly, most modern wheel cleaners are fairly benign. Older, really strong formulas...yea I remember them having a greater potential for discoloring the finish. It could have been that this particular rotor-hat paint didn't react well to the DUB formula, but it happened none the less. Otherwise, I saw no other damage. Still, it turned me off a little.