2013 with 20k miles. The black paint on the two exhaust cans are starting to come off. Not horrible at all, but if you step back and look at the back of the car, you can see the black paint is off on a small spot.

Would this be covered under warranty?

 

You can ask, but I doubt it. It's likely going to be considered normal wear as this is a part of the under carriage. If the missing paint causes corrosion to set in that might be a different story.