Factory classes

Can somebody explain what are factory classes good for? As in, "why all this shit"? I have the impression factory classes are yet another suit in the Emperor's wardrobe. To me, they always looked like some bored programmer who needs to keep his job and hates the KISS principle decided to make our lives worse.

Am I the only person lucky (or unlucky) enough to have used any number of languages in uni? Java, VB, C, C++, Prolog, Lisp, Tcl, asm?

This is overseas. Is the stuff in the US really going all Java?