Yoo hoo! Words have meaning. You did notice that I used the qualifier “in general,” correct? That means that I am a speaking of many, but not all, substitutes with whom I had experience.
I taught, by the way, for 22 years in a school district where 60+% of students were receiving either free or reduced price lunches— basically an inner city school district in the suburbs.
I had 30 years as a regular class room teacher, tutored for several years and taught across the economic and societal spectrum.