In the Seraphic Gate, no. Outside of it, yes. You can stock up on Base Metals which can turn into Ebony Powders which can turn into Material Potions. If you were to have 99 of each and planned to use them all, that would add up to 29,700 DME.
If you don't think it's obvious Haruhi likes Kyon, you're dense enough to be a male harem protagonist. http://www.youtube.com/view_play_list?p=ECA7F18CAAEACDEF