Why is there a complete homework and exercise tag, when all the question asked under that category are termed as off-topic. This tab accounts as the second largest tab but still the moderators down vote and also mark the topics under this tag even after providing a complete attempt done by the person who is asking the question. Why don't you people just discard the tag of 'homework and exercise'.
Second thing, do even conceptual question account for homework and exercise questions? Recently I just asked a simple question, whether the force in some direction should be zero or not, i even presented my own view and I didn't even ask the PSE to give me the complete answer to the question(I had only written the conceptual part in which I was facing problem) which I wanted to solve, still the question was regarded as belonging to homework and exercises. Pretty much abstruse!
The tag exists for people who don't want to see homework-motivated questions. They can ignore the tag to filter those questions out of their view.
As people pointed out in the comments, your premise that all homework-and-exercises questions are off topic is false. There are questions which are on topic and yet should have the tag, but it takes some care to ask such a question. In summary, it needs to ask about a concept (i.e. not for an answer or a procedure) and it needs to show how the concept in question emerges in the process of solving the problem. (This is part of what we consider "effort".)
That being said, our homework policy is changing soon. Perhaps at that point, we will get rid of the tag.