There are many issues in Islam where there is no clear consensus (covering women's faces for instance). Can someone ask and say something like "This is issue X. What are the arguments for it, and what are the arguments against?"
I think these questions ought to be allowed. They are precisely the types of questions experts ought to be asking.
However, I think it is usually (there are always exceptions) best to ask it as two questions; one question asking for the position in support of a position, and another asking for the position in opposition. This is usually best for the simple reason that it makes it possible to accept the best answer.
If you ask for both pro- and con- arguments for a single issue, you may end up with two correct answers, but can only accept one.
If you want both sides of an issue, I suggest asking two questions.
I think it would very much depend on how the question was worded. For example, the question in OP (i.e., What are the arguments for it, and what are the arguments against?) is just too close to a "list question" to really fit on the site. You're likely to end up with a bunch of partial answers explaining one particular argument (either for or against) but unlikely to ever get anything that resembles a canonical answer.
On the other hand, if the question were worded more like "Could someone explain the controversy surrounding issue X?", they are more likely to get a proper answer. Rather than just a list of arguments, which the first question is (technically) asking for, you're getting a breakdown on the controversy itself, why there is even a disagreement in the first place. Such an answer would (ideally) include sample evidences and arguments for both sides of the issue.
Obligatory blog link: http://blog.stackoverflow.com/2010/09/good-subjective-bad-subjective/
I think it is fine to ask about reasons and justifications for religious issues including clothing. There are lots of issues (almost every issue?) that there is not a consensus among Muslim scholars over them. Why should we not allow such questions?
On the other hand, debating or arguing over them on the site is not fine since this is not a forum, it is a Q&A site. Questions should be phrased politely and should be real question (not means to express one's opinion or criticize other people's opinions). Such questions can be closed as not-a-real-question (the OP doesn't really have a question although the post might use a question format) and/or not-constructive.