If there is a hair under the clear I find it highly unlikely its a factory job... the cars are sprayed in 'clean room' type conditions by a robotic process. Would be very very very hard for anything like that to make its way onto the car during spraying.
Seems like something is fishy - at some point it had to have had something unusual happen.
Not saying this is the case, but I do know of instances where a 'new' car was reshot at the dealer due to damage in transit. The car was hit by debris while on the trailer from the factory to the dealership. It was minor damage, but still nothing anyone would want on a new car so the dealership bodyshop repaired and resprayed the panels that were affected and the car was still sold as 'new'.