A Strange thought

Have you ever been drawn into the "why" game by a child? Every statement you make is met with another "why?" from the child. If you try to be a smartarse and answer every "why" you always end up saying "Because it is! Alright?"
This made me wonder, could centuries of scientific observation, experimentation and conceptualisation (if that's a word) bring us to the same conclusion.
Physicists are always striving to find out why. We even believe we know where the questions end. The grand unified theory which will unite atomic and classic physics. It's believed by many that it'll eventually take the form of a suspiciously simple equation. Once we know this, how would we answer anyone who points at it and asks why?
"Because it is! Alright?"