It's not just Subaru - Toyota paint sucks too for chips. I notice it's become worse in the last 4 or 5 years even though it's all been water-based for quite a while now. I just think they are using thinner coats to save weight (and cost). Don't laugh about the weight, I was amazed how much it adds to the weight of the car. And every ounce they can save gives them better mileage numbers.
Here's some info from SEMA on paint today...
http://www.sema.org/sema-enews/2012/...-auto-industry.