In every game other than Sonic Adventures 1/2, they refer to Robotnik as Robotnik, yet in the Sonic Adventure series, they call him Dr. Eggman. I know it's because he's called Eggman in Japan, but why didn't they call him Dr. Eggman in the first place?
Methinks Sega of America thought Robotnik sounded more menacing. :P

~ SA Tails