Why Are We Using Touch When.......

I've been dying to ask this question for a very long time, ever since the first day The         " RTM "  version of Windows 8 came out!

I've been seeing these " LAPTOPS " with touch - screen popping out everywhere. Not just from    " DELL " but from other manufacturers too. You can say that all of them have touchpads!

Why? I really don't get it! Why in the world do you need one of that " THING " if you have a  touch - screen!?!?

Thank You For Your Time & Have A Nice Day ;-)