I may put forward an educated guess here that the skin cancer rate in pilots is rather due to the increased amount of cosmic radiation (high energy gamma rays) rather than the UV light which is filtered out by first the actual windshield and than by the cool pilot's sunglasses...
As a SLF I rather prefer to fly in a plane where the pilots are able to quickly look up and see whats coming than as someone phrased it "flying submarine" or grandma's coffee parlor in the garden...