Exactly the point I was going to make... I seem to recall some comment from Rowling in an interview that not all the teachers live at Hogwarts (easy to commute in from Hogsmeade, after all, and not everyone eats at the Head Table). Nothing says there’s no Mr. Sprout or Mrs. Flitwick back home.
Hey if that wart Kuchinich can get a tall red head, Flitwick can sure do better!
I never said that was the case, I was responding to someone else.
But IF that is a “tradition”, then I don’t think it would stop
Harry from attempting to change it if he wanted to.