Isn't that where you go for a semi-massage.

 

I've noticed even from factory, with certain lighting, different body panels will show a slightly different color. For example look at your car on a hazy or cloudy day and notice the difference between the front bumper and the hood (I think this is where I noticed it). The different materials make the paint show slightly differently, which is amplified by certain lighting (usually heavy gray or spotty shadowing like through a tree).

 

flourecent lighting is the worst