Yes it's quite common for this to happen, I'd say even more than 10%
It sucks but considering how these cars are transported from the factory it's hardly surprising
One word though,
if it has had a respray then it's most likely that the front of the roof has been sprayed than the rear. It's really hard to replicate orange peel painting a car normally. BMWs are notorious for orange peel because of the way BMW prep and paint their cars. If your local bodyshop spray any part of your car you'll notice that there is hardly any orange peel left on the part they've painted.
I know as I've had the rear bumper and drivers rear 1/4 painted - it's the only bit of paint on the entire car that doesn't have orange peel!