New York vs. southwest fashion. Also, when he returns to NY to visit Pentangeli, he's formally attired.
I always felt that Michael intentionally always tried to break away from the stereotypical "gangster" persona. He preferred Packards and Chryslers over Cadillacs. He was always fashionably dressed, never flashy like his brother Fredo. He never acted like a "wiseguy". Remember he was educated at the prestigious Ivy League school Dartmouth.
