My thought is that I find the "disrespectful" concern to be silly. If it's a schoolwide policy, teachers are well aware that homework is only a tiny percentage of a student's grade and that many students will thus choose not to do it. It's been made a tiny percentage of their grade because it isn't super-important to do. A teacher who felt disrespected by students not doing something that has been objectively judged of little importance, would be unreasonable, I think. If Daughter is truly able to understand the material and maintain acceptable grades without doing the homework, more power to her. There's only two reasons to do homework that I can think of: 1) it helps kids learn and thus do better on other assignments, like tests; 2) it's necessary for their grades (that is, if they don't do it, serious points are lost). In Daughter's case, neither issue applies. She'd be better off using homework time to draw a nice picture for her teacher as a present, to show her affection and respect. Or, use that time to do chores around the house and thus show her respect for her mother and the family.
If Mom is concerned about the respect issue, why not ask the teacher directly? I'm surprised the adviser didn't suggest that, as usually they promote communication between parents and teachers. If the teacher hasn't given any signs they're upset about not receiving homework from Daughter, I don't know why Mom would be concerned anyway. But, if Mom has seen or heard something that makes her think the "disrespect" argument has merit, take it to the teacher for confirmation or denial. Related, I think it's odd the adviser suggested the teacher would think poorly of Daughter for not doing the homework--that she isn't a hard worker. What the heck, she's getting A's and B's. Do you want blood from this child? Does everything have to be 100% or else she's a failure? I might say, as Mom, "Okay, if the work is so easy for you, B's are no longer acceptable, it must be all A's." Or maybe look into enrichment or gifted activities, to make school more rigorous and interesting. If "hard work" is something they want to encourage, give her more challenging material, not pointless busywork. Maybe if it's a situation where they aren't counting just letter grades, but rather exact percentages to determine class rank, you could have an argument for a 97% A being better than a 93% A, but in my experience that usually only applies to high school, not middle school.
But, another important issue that wasn't touched on--Daughter might assess the situation and choose not to do the homework now, but she has to be willing to reassess and change should a different situation arise. Like if she gets a topic that she doesn't understand right away, or next year the material takes a leap beyond what she's comfortable with--at this age, I don't think she gets to choose to slump down to a B, when everyone knows she could get an A by doing reasonable additional work. So I would probably mention to her, "Okay, if you get comfortable ignoring homework now, will you be willing to do it when you actually need it?" In college, my homework was usually entirely optional and worth nothing, point-wise. But I quickly learned that for some classes, I needed practice in figuring out those problems, because the majority of the grade came from the exams, which were nothing BUT those problems. So if I hadn't done the homework just for learning, I wouldn't have done well on the exams. At 13 or whatever, she probably isn't thinking about that yet, so I would definitely talk about how she can know when she needs to do the homework, and not get caught up in never doing it or feeling bad for doing it. It's a resource there to help her succeed, and if she doesn't need it right now, great, but if she needs it in the future, she shouldn't hesitate to turn to it.
I keep thinking about this because I was a straight-A student all through public school. My school was not very rigorous, but I still worried and fretted about my grades, and I was under a lot of pressure by my parents and my peers to always have the highest grade, preferably a 100%. I would have done the homework without even considering NOT doing it, because I understood that a 93% was not good enough when I could have a 97%, even though both were A's. Once when I brought home a report card with an A- (A minus) my dad said, "That's almost a B," in a warning tone. The resources didn't exist to give me more challenging materials, apparently, and I was bored a lot of the time and used my classtime to write journal entries rather than pay attention to the teacher repeating something I already understood. (I have recently been digitizing those journal entries, so I can see exactly how much extra time I had!) So it was a combination of being bored but also knowing I had to do XYZ to get the highest possible percentage and never have a missing or late assignment (oh the shame). I was way more anxious about it than was reasonable, looking back, and I wouldn't want to encourage another student to get a skewed perspective like that.
If, when Daughter gets to high school, the exact percentage does become important, perhaps she will on her own decide to achieve more, relative to college acceptance and scholarships, or her parents could set a specific bar for some practical purpose (like this scholarship only applies to kids who rank in the top 10% of their class). Right now, in middle school, I'm guessing an A is an A still, so why put more pressure on her, again when the only way to "grow" the A is pointless busywork? Give her more challenging material or extra credit that will enrich her understanding if they want her to work harder at school.