My 2008 Itasca has the same problem. My body shop friend told me that the clear coat was probably applied too thinly. I also have it showing up at some storage bin doors and fender edges (actually it's thin paint and no clear coat). It's disappointing.
Most automobiles are painted with robots and the thickness of the paint and clear coat is carefully controlled, not with a guy standing on a ladder with a spray gun just before his break on Friday afternoon.
A real fix is $$$. My friend said that there are DIY 2-part rattle can clear-coat products available, that can help "fix" or more likely slow down the process. There's still quite a lot of prep work necessary and probably unsatisfactory results.