or not because fightsticks aren't a necessity to play fighters.
...a necessity to play all fighters.
I'd say most SF players I've talked to feel it just might be.
Where other fighters, or even within fighters like Soul Calibur - have different options, some good with pad, some not.
In SC - a versatile Taki or "A+K"/Button~Roll using character can be harder to play on a pad, while Hilde with her charges - BANNED - or a basic X or Mitsu can be played easily with a d-pad.
As for Xbox only fighters - plenty of DOA "hardcore" used the pad - so it's not that all fighters require them or not; there are definitely some who seem to, and some who just don't need it at all.
X A