I'm on the fence about screen protectors. I don't think they're necessary and I hate that I can still see the outline of the screen protector even when a user has installed the thinnest possible one. i think screens these days are pretty resilient right out of the box and only the most careless of users end up scratching their screens to the point where it's visibly noticeable.
But still, the screen protector industry is alive and well. People still get tricked into putting them on and now Apple and Belkin have teamed up to install screen protectors for you in-store. Using a new device from Belkin called the ScreenCare+ Application System, a phone is inserted into a machine and a screen protector is perfectly applied in one swooping motion. The machine itself is pretty neat and that's why I've posted a video of it below. But again, I think it's all totally unnecessary.