No, "좀 많이" is not disrespectful at all.
You could use it like "좀 많이 주세요" asking for generous portion of food, or you could say "좀 많이 나았어" when you were sick for a few days and your friend asks "how are you feeling today? got any better?", which means "I feel much better". 아마 드라마에서 사람들이 화를 낸 것은 미안하다라는 사과만으로 용서할 수 있는 상황이 아니었나봐요.