I'm starting to get sick of all these annoying 1-2 rebel unit-armies, that appears all too often. These battles are often sensless as you know you will leave the battlefield with a crushing victory, but still you rather play them than to auto-calculate them just to find out that your best general was killed.

So I was wondering if the rebels really do any damage to the province they are in? like lower income or something.
And why do the rebels appear? Does it have anything to do with the public order? Is there anyway to stop them for coming?