Imagine asking them to put it on after you purchase it, and them needing 3 attempts to get it on, and even then, it's not put on as well as it could be? The only advantage I can see is that they don't charge you for the replacements. Also, this screen protector is the dirtiest one you can get, it catches fingerprints horribly.
This is just a flimsy plastic screen that should NOT cost as much as it does. The installation didn't work either. I tried at home then brought it back and the guy in the store even said the tray and screen dont line up. Save your money and get a real glass screen protector.