I daresay that they (your teachers) are pretty mad at the fact that students are talking, disrupting the class, taking up time, (and effort, and energy, and attention), and, above all, by their behaviour, preventing others from learning.
One of the many reasons I (far) preferred third level teaching was not just that once could assume that students had chosen to study what you were trying (hoping) to teach them, but that you did not have to police them in class.
If my students (and this only happened - and then, very rarely - with giddy and excited first years, the students that Our Transatlantic Cousins refer to as "freshmen") acted up in class, I would remind them that I was a paid university teacher, not a police officer; it was not my task to impose discipline, or to ensure that they behaved like adults, and that they extended to me - and to their classmates - the courtesy and respect of treating each other with respect, as adults, and paying attention while attending class (and I always made time for questions during, and - preferably - at the end of, class), and, if they couldn't beothered to treat one another (and me) with respect, then, there was no point in attending class.
And, I would remind them, that id, as a consequence, their grades suffered, 1) this was not my fault, but theirs, and 2) this was their problem, not mine, and, in the meantime, I had a course that I wished to teach.
What age are you?
Injustice rankles, but you do sound young.
As a teacher, I was exceptionally sympathetic about extending deadlines for people with genuine stress and stuff in their lives, - any sort of illness (themselves or family), or single mothers, or kids from less well off backgrounds who worked to put themsleves through college, etc; I was a lot less sympathetic to individuals who had every advantage that life could cast upon them, yet still insisted on testing boundaries, and believing that rules (such as deadlines) applied to others.
Exactly.
No, it is not ridiculous.
Okay: I'll phrase it differently: How would you propose to deal with teenage idiots?