I use them for simple shortcuts they don't cover everything but your tutorial would have taken me 25 seconds. Now if I want to add flares and a haze effect that would take considerably more time. As far as unoriginal goes I think you may have it confused with the word Uncreative. As a professional artist time is important to my employers and often critical, if I can accomplish the exact same effect in one tenth the time why wouldn't I? For that matter why wouldn't anyone who seeks to do art on a professional level? I don't imply it's a better way but simply a huge time saver.
It's not about a time saver. You don't achieve good art by using other programs to do natural work. Good pieces take time, and it feels less "fake" to me to use natural filters and methods, then a program to press a couple buttons and then "done."