Arguments are important because many Judges avoid reading the entire case file (and, honestly, I can't blame them, given the volume of work and the fact that some of the pleadings being unreadable really). Even assuming a Judge has read the file, argruments still help in drawing the attention of the Court to the chief contentions of the party and precedents in support thereof (the classical rule of drafting insists that precedents should never be made a part of pleadings). Arguments may even otherwise help in building a perception in the mind of judicial officer in your favor and against the other party by presentation which cannot always be made a part of pleadings.
Written Arguments are also important becuase they bring on record the points for consideration raised by a party, which may assist in Appeals in showing that an important factor was brought to the notice of the Court but was not considered.
In your case if the Repondent is avoiding argument, all the better for you. Insist before the Court that since the Respondent is not willing to lead oral arguments, let the Court reserve final orders and permit the parties to file written arguments till a resonable time in the meanwhile, if they so choose (it is quite common).