Let's Make Robots!

PIC chips

Why not CPU's like intel or AMD instead of Microchip or Pickaxe and the like

First off I know very little about programing! But it seems to me that since there are tones of old CPUs around, many simply for the taking.

Why not use these on the larger complex Robots instead using two or three or more MCUs. 

But honestly I use one or two PIC chips on my small tinkerings. But I have larger project that I "think" I can see the CPU as being a much better fit. 

Am I missing something so fundamental that it boarders on the absurd?

Please, any I deas and feedbacks are welcome!

rccubed